ShellnoRoam problem with Softgrid 4.2

I experienced a strange occurence within an Citrix XenApp 4.5 environment delivering applications via Softgrid Client 4.2

The problem exhibited itself with the following symptoms :

User reports softgrid apps getting stuck at 100% Loaded but no launch
Users report slow responce on context menu options such as FILE
Server shows an increase in context switches
Server shows an increase in page faults
Server shows an increase in CPU useage for the user reporting the issue

Monitoring showed what appears to be a loop on reading the following registry key
HKCU\Software\Microsoft\Windows\ShellNoRoam

The default key was populated with the name of the terminal server. This appears to get populated by a variety of applications. (IE, Explorer)

Deleting the value contained in the key sets the key value to (value not set)
This action appears to resolve the issue, and all the symptoms listed above are resolved for that user.

The problem is that the key can get easily repopulated again with the terminal server name if the user launches another application.

Softgrid say that this is an known issue and is resolved in SoftGrid 4.5 (App-V Client)

An upgrade is not an option for my environment at present so as a short term fix to prevent this occuring I have used the Appsense SelfHeal function to ensure the key remains blank. An alternative would be to remove permissions to this registry key for Users, though i have not tested that option.

I have more detail on the shellnoroam key being populated with the servername now. Please see seperate blog for explanation.