I upgraded to Firefox 3.6, and now the Zotero 1.0 extension is not working. How do I locate the Zotero directory to back up before I upgrade to Zotero 2.0
well - windows has localized folder structures, so how it looks exactly depends on the language - the above should give you an idea of where to look, though. This part \Mozilla\Firefox\Profiles\\zotero is universal, so if you're able to find that you'll be good. Also, a search for the file zotero.sqlite on the entire harddisk, including hidden files and folders should get you there.
C:\Documents and Settings\<username>\Application Data\Mozilla\Firefox\Profiles\<randomstring>\zotero
However, there is no C:\Documents and Settings\<username>\Application Data\ folder in my PC.
This part \Mozilla\Firefox\Profiles\\zotero
is universal, so if you're able to find that you'll be good.
Also, a search for the file zotero.sqlite on the entire harddisk, including hidden files and folders should get you there.