Forms authentication failed for the request.

Hi,

Im expriens a strange problem, and know its a common problem, so i hope someone can help me.

-Im developing in a comunity-site, but gets an error and the site also do a "logout" of the current user logged in. The happens often on deleting a blogpost, aproxly on every 1. or 3. delete.

After searhing the net, if figured out that it properly has something to do with the Forms-Authentication, that get messed up.

Im getting this error in the system event log.

Event Type: Information
Event Source: ASP.NET 2.0.50727.0
Event Category: Web Event
Event ID: 1315
Date:  30-10-2008
Time:  14:15:57
User:  N/A
Computer: WS1110
Description:
Event code: 4005
Event message: Forms authentication failed for the request. Reason: The ticket supplied has expired.
Event time: 30-10-2008 14:15:57
Event time (UTC): 30-10-2008 13:15:57 ...