perhaps the problem is in syncing, because some time ago I played with online database for zotero via ipod touch, but I removed all this and deactivated syncing zotero account
Given that this happens in a new document, I'm afraid there's nothing more we can tell you. It's something on your system outside of Zotero — nothing to do with Zotero settings, syncing, or anything remotely like that. You'll have to experiment, or try another user account, or try another computer.
Your best recourse would be to sync your Zotero account with another computer (and/or install Zotero on a separate user account on your computer) and try to update your document then. As dstillman says, the symptoms you've described indicate that it is a problem with your system, not with any of Zotero's settings.
This is an old thread, but I had a very similar problem that got solved by turning off tracked changes in Word 2010 before attempting to Add/Edit a citation.
"http://zotero.org/users/XXXXX/items/YYYYY"
how to remove that?