Enable RemoteApp on Server 2008/Windows 7

We have two Citrix farms, a XenApp 5 farm and a XenApp 6 farm.  XenApp 6 only supports 64bit OS's.

We have some applications that will not operate on a 64bit OS (Microsoft FRx).  Since we want to decommission our old Citrix XenApp 5 farm because we're moving to XenApp 6/6.5 we need a solution.  The solution I have come up with is to use Microsoft RemoteApp functionality to publish this application through XenApp 6.  I've come across this blog post that details how to do it, but I'm going to summarize the technical changes here:

Step 1

Run regedit (registry editor) and locate the key TsAppAllowList

     a) New Key, Applications.
     b) Under Applications, create New Key, 1234567 (the key name is not important, we just need any key for next two steps)
     c) In the new key, Create New -> String Value, Name. Set value to Notepad
     d) Also in the new key, Create New -> String Value, Path. Set to c:\windows\system32\Notepad.exe

Navigate back to the TsAppAllowList branch
     a) Edit fDisableAllowList value, and set to 1


Step 2 – Creating the RDP file to access the RemoteApp
Now the guest operating system has a RemoteApp created we need to use a Remote Desktop Connection to access that application.
1. Run remote desktop connection, setup your desired settings as you would in a normal connection
2. Save the settings to an RDP file.
 
3) Use Notepad to open the RDP file to edit the configuration file,
   a) Modify the setting; remoteapplicationmode:i:0  to  remoteapplicationmode:i:1
   b) Add the setting; remoteapplicationprogram:s:Notepad
   c) Add the setting; disableremoteappcapscheck:i:1
   d) Add the setting; alternate shell:s:rdpinit.exe
   e) Save the RDP file


Final thought
Similar to VirtualBox seamless mode, you will not be able to move the floating guest application window between monitors, unless you save the RDP to use all monitors available.  Either set this option prior to saving the RDP file, or edit the RDP setting multimon:i:1.