Bad security token?

[draggar]

I get this error message sometimes when I'm trying to post or edit one of my posts:

Your submission could not be processed because a security token was missing.
If this occurred unexpectedly, please inform the administrator and describe the action you performed before you received this error.

I don't know if it is my work's security or something w/ the forum - I don't think I had this issue at home.

Did this forum do the big VBulltien update that came out recently?