Outlook 2010 - "The custom form cannot be opened"

Hello,

We've got several users who claim that, when opening an EV item, it appears the message:

"The custom form cannot be opened. Outlook will use an Outlook form instead. The form required to view this message cannot be displayed. Contact your administrator."

Tried the following:

- Cleared the cached forms,

- Renamed FRMCACHE.DAT to FRMCACHE.old,

- Recreated Outlook profile,

No sucess. User's don't and can't have acess to administrative permission in any files on Registry. The only thing i came up with was to re-create the whole user windows profle, which it worked.

The computers are Windows XP with SP3 installed and EV v10.0.17573.

Does anyone have other tips or solutions for this problem, besides having to re-create the whole profile ?

Thanks in advance !