Be careful, Zotero users: the Zotero add-on likes to store proxy URLs to help off-campus users access library resources without going through the library's website (http://www.zotero.org/support/proxies). By storing the proxy URL, an off-campus user only has to go through library channels once (in theory).
The critical problem with this occurs when we update our proxy URLs. No matter how you get to that resource, Zotero will automatically re-write your URL to the stored proxy url. So unless you go into the Zotero add-on's proxy url settings and update or delete the old url, you'll be redirected to a link that is most likely dead.
The SciEng Reference Desk had a number of resources that were mysteriously inaccessible (Ebsco, Ovid, and Engineering Village resources) or behaving strangely until we discovered that Zotero was the culprit.
The solution: you can disable Zotero, but better yet, you can tell Zotero not to automatically store proxy urls. If you're in Firefox, go to Tools > Add-ons. Click on Extensions (if it's not showing already), then scroll down to Zotero. This is how you get into Zotero Options. In Options, click on the Proxies tab. Then uncheck "Automatically remember proxied resources." At this stage, you might want to also delete any stored proxy urls. Restart Firefox.
Thanks to Michael Winters, Shane Nackerud and Michael Johnson for helping to uncover this issue.
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