title: How to use launch condition option in installation package using C#
body: <p>I want my application to check (before start installation) for <strong>Nokia_PC_Suite_rel_7_0_8_2</strong>
  my steps are :</p>
  
  <p>1) I added Registry Search and it's properties are </p>
  
  <pre><code>Property = PCSUITERUNTIMEEXISTS, RegKey = HKEY_LOCAL_MACHINE\SOFTWARE\PCSuite\Product, Root= vsdrrHKLM, Value = Nokia Pc Suite
  </code></pre>
  
  <p>NOTE: I got the value of <code>Value</code> property from the registry editor were i double-clicked on PCSiute then I found Product when I clicked on it I found a dialogue with 2 texts: </p>
  
  <ol>
  <li>Value name</li>
  <li>Value data</li>
  </ol>
  
  <p>2) I added new Launch condition called "PCSuite Runtime installed, if not prompt user"
  and its properties are :</p>
  
  <pre><code>    condition = PCSUITERUNTIMEEXISTS //(it's a drop down list so I selected the condition I created in "Registry Search"), 
  Messege = [ProductName] requires Nokia_PC_Suite_rel_7_0_8_2  runtime. 
  Please run setup.exe to install the prerequisites for this application.
  </code></pre>
  
  <p>Now in setup.exe I added Nokia_PC_Suite_rel_7_0_8_2.exe as a pre-requisites so when the user double-clicked on setup.exe he will ask him to install Nokia_PC_Suite_rel_7_0_8_2 if he cancelled the whole installation will stop.</p>
  
  <p>What really happens is that when I click on .msi file is always displays the message ("[ProductName] requires Nokia_PC_Suite_rel_7_0_8_2  runtime. Please run setup.exe to install the prerequisites for this application.") although there is PCSuite Version installed on my PC.</p>
  
  <p>So what to do? I want him to continue the installation if he found PCSuite if not display the message so the user will go to setup.exe.
  Also when I un-installed PCSuite and clicked onsetup.exe it started installing PCSuite and when he finished he displayed the previous message and quit from the installation.</p>