I am getting quite a lot of Oops! Something Bad Happened! while editing existing posts. It seems to occur only when trying to update posts, not when creating a new one. It seems to occur when I first create a new post, then immediately after saving click the "edit" link to change it again, and then try to save those changes.
One example of error page URL: https://stackoverflow.com/error?aspxerrorpath=/posts/2662048/edit-submit/32cc6a03-b1e3-4146-a382-679e32ab67e6
If I press the back button and try to submit again, I get the same error again. If I go back to answer list and refresh the page, the editing works.
I am using Windows Vista and Google Chrome. This does not happen every time, but often enough to be annoying. This error has started to appear only recently.
I am also experiencing errors in ajax stuff like voting, see this question, for more details.
Edit: I got this error again after about 3-5 tries in SO. HTML comments have this error msg. URL for error page is this https://stackoverflow.com/error?aspxerrorpath=/posts/2767030/edit-submit/ff34ea58-e917-411e-92bc-a45f59710553
XSRF validation: Request form value 'fkey' did not match CurrentUser.XSRFFormValue
Edit: I experimented with editing tags. This problem occurs with Google Crome 220.127.116.114 (45376), but does not occur with Firefox 3.6.3. I made same steps in both: make a search, go to question, edit tags, click back buttons until back in search results, go to question etc. Repeat many times.
I do not have any extensions installed in Chrome. I used same Vista machine with Firefox and Chrome. So is Chrome losing my cookie all the time, or what is wrong? I don't see how this could be networking related, like Atwood suggested.