:: Clear plugin cache (common fix for "cannot launch app") del /q "%USERPROFILE%\AppData\Local\Citrix\Plugins\Cache*.*"
:: Check installed plugin versions (Windows) reg query "HKLM\SOFTWARE\Citrix\Plugins\XenApp" /v Version :: Verify ActiveX control is registered reg query "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\wfica32.exe"
:: Re-register the control (IE 32-bit only) regsvr32 "C:\Program Files (x86)\Citrix\ICAClient\Plugins\wficat.cab\wfica.ocx" For its time (2005–2012), the XenApp Web Plugin was a clever solution. It turned a clunky ICA file download into a one-click web experience. But by 2015, it was a legacy liability—an insecure, browser-bound bottleneck.
Have you inherited a XenApp 6.5 environment? Share your war stories in the comments.
Do not invest time in fixing it. Invest time in migrating off it. Modern Citrix Workspace app + StoreFront or HTML5 access is faster, more secure, and infinitely less frustrating.