If you notice that you are getting logged out occasionally when going from page to page, chances are you have a corrupt cookie.
Sometimes, the computer cookies become corrupt and just stop working. You can set them all day, but they still don't quite function properly.
What is necessary is to get rid of the corrupt cookie before
you ask the server to give you a new one.
You also may need to clear your internet cache. Here are instructions on clearing your cache for the most popular browsers:
In Internet Explorer:
On the Internet Explorer Tools menu, click Internet Options
. The Internet Options box should open to the General
On the General
tab, in the Temporary Internet Files
section, click the Delete Files
button. This will delete all the files that are currently stored in your cache.
Click OK, and then click OK again.
In Mozilla Firefox:
Select "Tools", "Options", then "Privacy". Cick the "Clear" button next to Cache.