Does Zotero purge library content from inactive accounts after a period of time?
I have just returned to Zotero after an absence of several years. My username and email have been recognized, and I was able to change my password, having forgotten the last one used. But when I go to the Library, I do not find any files. I had several there when a last accessed Zotero. Is that material recoverable or gone forever?
You can search your computer for zotero.sqlite files to see if there's a Zotero data directory somewhere on your computer that somehow got orphaned. (That page also lists the default locations from previous versions.)
My bad.
But if it's really a Zotero 2.0 database, you won't be able to open it in Zotero 5.0 and would need to install Zotero 4.0 from the download page first to upgrade it and then upgrade to Zotero 5.0. (What makes you think it's Zotero 2.0, though? That would be from 2010…)