I seared for and located your web page where someone had exactly the same problem. Their publish was xhtml Search Form giving errors via Validator, need some help? [closed] was closed without any solution. I have a similar problem. After I close Ie it provides me with the folowing error several occasions:

Message: Object required
Line: 53
Char: 3
Code: 0
URI: 

After I checked using the Explorer Developer Tools Line 53 may be the search form code. Would actually appreciate outside assistance because it is very annoying. Thanks.

Object is most likely mentioning to some missing object from the class within the php, in a guess from that which you have stated, perhaps you have edited the search script whatsoever?

Hi just reply. No I didn't edit the search script, however i found another questions from individuals who had exactly the same problem and located some instructions on resetting plug ins on http://codex.wordpress.org/. It gave two techniques, one via FTP that we attempted since it was simpler than doing the work 1 by 1 individually and also the error disappeared. Thanks.