We recently rolled out Chrome in our enviroment , a user’s default browser went back to IE one day. On going to default programs in Control Panel , HTTP/URL links where all defaulted to Citrix Metaframe Server FTA and greyed out. This task is responsible for redircting http traffic to the local client for Flash Redirection/Rendering however this does not work with Chrome.

Trying to set these back to chrome would not work using the GUI. For some reason the Chrome Icon in the default programs was not showing either. This was not a local machine ( HKLM or HKCR )or server problem as other users logging into the machine could default to Chrome fine.

In the end, to reset the defaults, I had to delete this key for the user and reset the defaults via the GUI

HKEY_CURRENT_USER\Software\Classes