From your description, in your ASP.NET 2.0 web application which use forms
authentication, it will report the following error,correct?
Event code: 4005
Event message: Forms authentication failed for the request. Reason: The
supplied has expired.
As for the ticket expired issue, is it frequently occuring or just occur
after a long time or randomly? Also, is your ASP.NET web application hosted
as a webfarm model? Based on my quick research, there are some existing
issue with the similar symptom:
** When your ASP.NET application using Formsauthentitcation hosted in
webfarm environment, and if you haven't manually specify the machinekey,
the authentication ticket encrypted by one server will fail to be valid on
** Another possible scenario is when the forms authentication based
application has restart or recycle, then the previous generated ticket will
fail to be decrypted by the new application instance(since autogenerated
machinekey will vary between different application instance).
Here are two web articles you can refer to:
and to better understand how the forms authentication and its ticket works,
you can have a look at the following reference:
#Explained: Forms Authentication in ASP.NET 2.0
#Understanding the Forms Authentication Ticket and Cookie
Hope this helps.
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