user19892: I use visual Micro for Visual Studio. Out of nowhere, I can't compile for any board. I tried a blink sketch for the nano, and I get intelisense red underlines for simple things like pinMode, digitalWrite, and Serial.print. Here's what I get for an output:
Compiling debug version of 'Nano_Trials' for 'Arduino Nano w/ ATmega328'
Build folder: file:///C:/Users/jf051e/AppData/Local/V.Micro/Arduino/Builds/Nano_Trials/nano_atmega328
Additional Defines: VM_DEBUG;VM_DEBUG_ENABLE 1;VM_DEBUG_BANDWIDTH_THROTTLE_MS 50;VM_DEBUGGER_TYPE_HARDWARESERIAL 0;VM_DEBUGGER_TYPE_SOFTWARESERIAL 1;VM_DEBUGGER_TYPE_FASTSERIAL 2;VM_DEBUGGER_TYPE_USB 3;VM_DEBUGGER_TYPE_TEENSY 4;VM_DEBUGGER_TYPE_UART 5;VM_DEBUGGER_TYPE_USART 6;VM_DEBUGGER_TYPE_USBSERIAL 7;VM_DEBUGGER_TYPE_TTYUART 8;VM_DEBUGGER_TYPE_NET_CONSOLE 9;VM_DEBUGGER_TYPE_Uart 10;VM_DEBUGGER_TYPE_COSA 11;VM_DEBUGGER_TYPE_CDCSerialClass 12;VM_DEBUGGER_TYPE VM_DEBUGGER_TYPE_HARDWARESERIAL;VM_DEBUG_BREAKPAUSE;
Architecture Tools: {runtime.tools.avr-gcc.path}/bin/
Sketchbook: file:\\\C:\Users\jf051e\Documents\Arduino
Sketch Include Paths
Include Path 'C:\Users\jf051e\Documents\Arduino\Nano_Trials'
Core Include Paths
Include Path 'C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino'
Include Path 'C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs'
Library Include Paths (1)
"{runtime.tools.avr-gcc.path}\bin\avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\Nano_Trials.cpp" -o "nul"
The system cannot find the file specified
    Preprocess: "{runtime.tools.avr-gcc.path}\bin\avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\Nano_Trials.cpp" -o "nul"
Unknown error during deep search source code for includes. Attempting alternative regex exploration
System.NullReferenceException: Object reference not set to an instance of an object.
   at Visual.Micro.MiroAppAPI.SketchCompilerArduino._TryRunPreProcessIncludesDiscoveryUntilDone(String sourceFilePath, Board brd, List`1 includePaths, Boolean isTopLevel)
   at Visual.Micro.MiroAppAPI.SketchCompilerArduino.TryRunPreProcessIncludesDiscoveryUntilDone(String sourceFilePath, Board brd, List`1 includePaths, SketchLibraryList knownLibs)
   at Visual.Micro.MiroAppAPI.SketchCompilerArduino._compile(SketchBuilder lsketch, String primaryClassName, Boolean verbose, Boolean isDebug)
Library Include Paths (1)
Build Core Paths: C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino
Using library VM_DBG version 0.0.0 in folder C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG
"{runtime.tools.avr-gcc.path}/bin/avr-g++" -c -g -Os -Wall -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Arduino\libraries" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries" -I"C:\Users\jf051e\Documents\Arduino\libraries" "C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG\VM_DBG.cpp" -o "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\VM_DBG\VM_DBG.cpp.o" -DVM_DEBUG -DVM_DEBUG_ENABLE=1 -DVM_DEBUG_BANDWIDTH_THROTTLE_MS=50 -DVM_DEBUGGER_TYPE_HARDWARESERIAL=0 -DVM_DEBUGGER_TYPE_SOFTWARESERIAL=1 -DVM_DEBUGGER_TYPE_FASTSERIAL=2 -DVM_DEBUGGER_TYPE_USB=3 -DVM_DEBUGGER_TYPE_TEENSY=4 -DVM_DEBUGGER_TYPE_UART=5 -DVM_DEBUGGER_TYPE_USART=6 -DVM_DEBUGGER_TYPE_USBSERIAL=7 -DVM_DEBUGGER_TYPE_TTYUART=8 -DVM_DEBUGGER_TYPE_NET_CONSOLE=9 -DVM_DEBUGGER_TYPE_Uart=10 -DVM_DEBUGGER_TYPE_COSA=11 -DVM_DEBUGGER_TYPE_CDCSerialClass=12 -DVM_DEBUGGER_TYPE=VM_DEBUGGER_TYPE_HARDWARESERIAL -DVM_DEBUG_BREAKPAUSE
The system cannot find the file specified
    Process: "{runtime.tools.avr-gcc.path}\bin\avr-g++" -c -g -Os -Wall -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Arduino\libraries" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries" -I"C:\Users\jf051e\Documents\Arduino\libraries" "C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG\VM_DBG.cpp" -o "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\VM_DBG\VM_DBG.cpp.o" -DVM_DEBUG -DVM_DEBUG_ENABLE=1 -DVM_DEBUG_BANDWIDTH_THROTTLE_MS=50 -DVM_DEBUGGER_TYPE_HARDWARESERIAL=0 -DVM_DEBUGGER_TYPE_SOFTWARESERIAL=1 -DVM_DEBUGGER_TYPE_FASTSERIAL=2 -DVM_DEBUGGER_TYPE_USB=3 -DVM_DEBUGGER_TYPE_TEENSY=4 -DVM_DEBUGGER_TYPE_UART=5 -DVM_DEBUGGER_TYPE_USART=6 -DVM_DEBUGGER_TYPE_USBSERIAL=7 -DVM_DEBUGGER_TYPE_TTYUART=8 -DVM_DEBUGGER_TYPE_NET_CONSOLE=9 -DVM_DEBUGGER_TYPE_Uart=10 -DVM_DEBUGGER_TYPE_COSA=11 -DVM_DEBUGGER_TYPE_CDCSerialClass=12 -DVM_DEBUGGER_TYPE=VM_DEBUGGER_TYPE_HARDWARESERIAL -DVM_DEBUG_BREAKPAUSE
Error compiling libraries

I swear I didn't touch anything. i was working on a different sketch and when I hit compile, Visual Studio froze and said it was busy. i had to kill the process and try again. I did this like 8 times before i realized that I could do longer compile ANY sketch. I even restarted my PC to no avail. What the heck??

user11548: There are a few suggestions here, here and here:

Ensure you are using the latest Arduino software that is compatible with Visual Micro (this is not necessarily the latest Arduino software!)

Go to Visual Micro menu -> Board pulldown -> Find or install a
board--> Rescan. You should get "Toolchain reload complete". The
Visual Micro forum administrator suggests that you do this twice.

Reset the User's Appdata Arduino folder



Close all IDE's

Delete the C:\Users<USERNAME>\AppData\Local\Arduino15 folder

Start the Arduino IDE once. Close after it has fully started

Then try Visual Micro again



Delete the preferences.txt file (if it exists)
Goto C:\Users<USERNAME>\AppData\Roaming\Arduino and delete the preferences.txt file.


user19892: So I seem to have fixed it. One way or another, I think VisualMicro suffered some type of problem with the installed boards. My first clue was that my sketches still compiled int the native Arduino IDE. So I went into the VisualMicro explorer and noticed that there was an update to 1.6.19 in the board manager (I was running 1.6.13). I don't know exactly what the problem was, but installing the update to 1.6.19 seems to have fixed it. 

19892: <p>I use visual Micro for Visual Studio. Out of nowhere, I can't compile for any board. I tried a blink sketch for the nano, and I get intelisense red underlines for simple things like pinMode, digitalWrite, and Serial.print. Here's what I get for an output:</p>

<pre><code>Compiling debug version of 'Nano_Trials' for 'Arduino Nano w/ ATmega328'
Build folder: file:///C:/Users/jf051e/AppData/Local/V.Micro/Arduino/Builds/Nano_Trials/nano_atmega328
Additional Defines: VM_DEBUG;VM_DEBUG_ENABLE 1;VM_DEBUG_BANDWIDTH_THROTTLE_MS 50;VM_DEBUGGER_TYPE_HARDWARESERIAL 0;VM_DEBUGGER_TYPE_SOFTWARESERIAL 1;VM_DEBUGGER_TYPE_FASTSERIAL 2;VM_DEBUGGER_TYPE_USB 3;VM_DEBUGGER_TYPE_TEENSY 4;VM_DEBUGGER_TYPE_UART 5;VM_DEBUGGER_TYPE_USART 6;VM_DEBUGGER_TYPE_USBSERIAL 7;VM_DEBUGGER_TYPE_TTYUART 8;VM_DEBUGGER_TYPE_NET_CONSOLE 9;VM_DEBUGGER_TYPE_Uart 10;VM_DEBUGGER_TYPE_COSA 11;VM_DEBUGGER_TYPE_CDCSerialClass 12;VM_DEBUGGER_TYPE VM_DEBUGGER_TYPE_HARDWARESERIAL;VM_DEBUG_BREAKPAUSE;
Architecture Tools: {runtime.tools.avr-gcc.path}/bin/
Sketchbook: file:\\\C:\Users\jf051e\Documents\Arduino
Sketch Include Paths
Include Path 'C:\Users\jf051e\Documents\Arduino\Nano_Trials'
Core Include Paths
Include Path 'C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino'
Include Path 'C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs'
Library Include Paths (1)
"{runtime.tools.avr-gcc.path}\bin\avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\Nano_Trials.cpp" -o "nul"
The system cannot find the file specified
    Preprocess: "{runtime.tools.avr-gcc.path}\bin\avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\Nano_Trials.cpp" -o "nul"
Unknown error during deep search source code for includes. Attempting alternative regex exploration
System.NullReferenceException: Object reference not set to an instance of an object.
   at Visual.Micro.MiroAppAPI.SketchCompilerArduino._TryRunPreProcessIncludesDiscoveryUntilDone(String sourceFilePath, Board brd, List`1 includePaths, Boolean isTopLevel)
   at Visual.Micro.MiroAppAPI.SketchCompilerArduino.TryRunPreProcessIncludesDiscoveryUntilDone(String sourceFilePath, Board brd, List`1 includePaths, SketchLibraryList knownLibs)
   at Visual.Micro.MiroAppAPI.SketchCompilerArduino._compile(SketchBuilder lsketch, String primaryClassName, Boolean verbose, Boolean isDebug)
Library Include Paths (1)
Build Core Paths: C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino
Using library VM_DBG version 0.0.0 in folder C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG
"{runtime.tools.avr-gcc.path}/bin/avr-g++" -c -g -Os -Wall -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Arduino\libraries" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries" -I"C:\Users\jf051e\Documents\Arduino\libraries" "C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG\VM_DBG.cpp" -o "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\VM_DBG\VM_DBG.cpp.o" -DVM_DEBUG -DVM_DEBUG_ENABLE=1 -DVM_DEBUG_BANDWIDTH_THROTTLE_MS=50 -DVM_DEBUGGER_TYPE_HARDWARESERIAL=0 -DVM_DEBUGGER_TYPE_SOFTWARESERIAL=1 -DVM_DEBUGGER_TYPE_FASTSERIAL=2 -DVM_DEBUGGER_TYPE_USB=3 -DVM_DEBUGGER_TYPE_TEENSY=4 -DVM_DEBUGGER_TYPE_UART=5 -DVM_DEBUGGER_TYPE_USART=6 -DVM_DEBUGGER_TYPE_USBSERIAL=7 -DVM_DEBUGGER_TYPE_TTYUART=8 -DVM_DEBUGGER_TYPE_NET_CONSOLE=9 -DVM_DEBUGGER_TYPE_Uart=10 -DVM_DEBUGGER_TYPE_COSA=11 -DVM_DEBUGGER_TYPE_CDCSerialClass=12 -DVM_DEBUGGER_TYPE=VM_DEBUGGER_TYPE_HARDWARESERIAL -DVM_DEBUG_BREAKPAUSE
The system cannot find the file specified
    Process: "{runtime.tools.avr-gcc.path}\bin\avr-g++" -c -g -Os -Wall -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=106011 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\variants\eightanaloginputs" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG" -I"C:\Program Files (x86)\Arduino\libraries" -I"C:\Program Files (x86)\Arduino\hardware\arduino\avr\libraries" -I"C:\Users\jf051e\Documents\Arduino\libraries" "C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\zq2favuv.ley\Micro Platforms\default\debuggers\VM_DBG\VM_DBG.cpp" -o "C:\Users\jf051e\AppData\Local\V.Micro\Arduino\Builds\Nano_Trials\nano_atmega328\VM_DBG\VM_DBG.cpp.o" -DVM_DEBUG -DVM_DEBUG_ENABLE=1 -DVM_DEBUG_BANDWIDTH_THROTTLE_MS=50 -DVM_DEBUGGER_TYPE_HARDWARESERIAL=0 -DVM_DEBUGGER_TYPE_SOFTWARESERIAL=1 -DVM_DEBUGGER_TYPE_FASTSERIAL=2 -DVM_DEBUGGER_TYPE_USB=3 -DVM_DEBUGGER_TYPE_TEENSY=4 -DVM_DEBUGGER_TYPE_UART=5 -DVM_DEBUGGER_TYPE_USART=6 -DVM_DEBUGGER_TYPE_USBSERIAL=7 -DVM_DEBUGGER_TYPE_TTYUART=8 -DVM_DEBUGGER_TYPE_NET_CONSOLE=9 -DVM_DEBUGGER_TYPE_Uart=10 -DVM_DEBUGGER_TYPE_COSA=11 -DVM_DEBUGGER_TYPE_CDCSerialClass=12 -DVM_DEBUGGER_TYPE=VM_DEBUGGER_TYPE_HARDWARESERIAL -DVM_DEBUG_BREAKPAUSE
Error compiling libraries
</code></pre>

<p>I swear I didn't touch anything. i was working on a different sketch and when I hit compile, Visual Studio froze and said it was busy. i had to kill the process and try again. I did this like 8 times before i realized that I could do longer compile ANY sketch. I even restarted my PC to no avail. What the heck??</p>
 11548: <p>There are a few suggestions <a href="http://forum.arduino.cc/index.php?topic=313176.0" rel="nofollow noreferrer">here</a>, <a href="http://www.visualmicro.com/forums/YaBB.pl?num=1490350071" rel="nofollow noreferrer">here</a> and <a href="http://www.visualmicro.com/forums/YaBB.pl?num=1473023621#top" rel="nofollow noreferrer">here</a>:</p>
<ol>
<li><p>Ensure you are using the latest Arduino software <em>that is compatible with Visual Micro</em> (this is not necessarily the latest Arduino software!)</p>
</li>
<li><p>Go to Visual Micro menu -&gt; Board pulldown -&gt; Find or install a
board--&gt; Rescan. You should get &quot;Toolchain reload complete&quot;. The
Visual Micro forum administrator suggests that you do this twice.</p>
</li>
<li><p>Reset the User's Appdata Arduino folder</p>
</li>
</ol>
<ul>
<li><p>Close all IDE's</p>
</li>
<li><p>Delete the C:\Users&lt;USERNAME&gt;\AppData\Local\Arduino15 folder</p>
</li>
<li><p>Start the Arduino IDE once. Close after it has fully started</p>
</li>
<li><p>Then try Visual Micro again</p>
</li>
</ul>
<ol start="4">
<li>Delete the preferences.txt file (if it exists)
Goto C:\Users&lt;USERNAME&gt;\AppData\Roaming\Arduino and delete the preferences.txt file.</li>
</ol>
 19892: <p>So I seem to have fixed it. One way or another, I think VisualMicro suffered some type of problem with the installed boards. My first clue was that my sketches still compiled int the native Arduino IDE. So I went into the VisualMicro explorer and noticed that there was an update to 1.6.19 in the board manager (I was running 1.6.13). I don't know exactly what the problem was, but installing the update to 1.6.19 seems to have fixed it. </p>
