title: The most basic docker build fails on COPY
body: <p>I'm trying to build a docker image for this first time out of the exeutables for a VS project that is already compiled. I do not want docker to build my project (oh no given the problems I already have). As a result I have the following Dockerfile in the folder where my app source files (and compiled binaries) are:</p>
  
  <p>Location: <code>d:\MyApp</code></p>
  
  <p>Dockerfile Contents:</p>
  
  <pre><code>FROM microsoft/windowsservercore
  COPY bin /app
  ENTRYPOINT ["C:\\app\\x86\\Debug\\MyApp.exe"]
  </code></pre>
  
  <p>Contents of MyApp folder:</p>
  
  <pre><code>MyApp\
  MyApp\bin
  MyApp\bin\x64
  MyApp\bin\x64\Release
  MyApp\bin\x64\Debug
  MyApp\bin\x64\Release\* (lots of binaries)
  MyApp\bin\x64\Debug\* (lots of binaries)
  ...
  MyApp\Dockerfile
  </code></pre>
  
  <p>Command window:</p>
  
  <pre><code>d:\MyApp&gt; docker image build .
  
  Sending build context to Docker daemon 3.584kB
  Step 1/3 : FROM microsoft/windowsservercore  ---&gt; 4dba31379dad
  Step 2/3 : COPY bin /app COPY failed: CreateFile \\?\C:\ProgramData\Docker\tmp\docker-builder196938557\bin: The system cannot find the file specified.
  </code></pre>
  
  <p>If I change the COPY line to <code>COPY ./bin/*.* /app/</code> :</p>
  
  <pre><code>Sending build context to Docker daemon  3.584kB
  Step 1/3 : FROM microsoft/windowsservercore
   ---&gt; 4dba31379dad
  Step 2/3 : COPY ./bin/*.* /app/
  COPY failed: no source files were specified
  </code></pre>