I've got a Site connected to a Partner Portal, and if the user logs in on a browser, then closes the tab, then opens a new tab to login again, they are kicked out the VisualForce error page after they enter their credentials.  They will be continually kicked out the error page on login attempts until their original session times out.  This seems to be related to cookies or the session tracking in the browser because if they try to login via another browser, or if they clear their browser cache, they are able to login successfully.

Any suggestions?

I've run into a problem with deleting from a custom object enhanced list view.  I click delete and get a confirmation popup, but then it takes me to a page saying "The attempted delete was invalid for your session. Please confirm your delete." From there, is does allow me to delete the object.

Is there anything that I can do to avoid this secondary confirmation?

I've got a Site connected to a Partner Portal, and if the user logs in on a browser, then closes the tab, then opens a new tab to login again, they are kicked out the VisualForce error page after they enter their credentials.  They will be continually kicked out the error page on login attempts until their original session times out.  This seems to be related to cookies or the session tracking in the browser because if they try to login via another browser, or if they clear their browser cache, they are able to login successfully.

Any suggestions?