Zotero is a web-based citation manager that makes it easy to collect citations from anywhere on the web.
It has a browser extension called "Zotero connector" which, when enabled allows you to more easily collect citations from web content and the library. This connector also can automatically detect proxy settings and store them for you for future use. Unfortunately, if not configured correctly, this service can interfere with your ability to access content from Muhlenberg.
The rest of this guide will describe the issues and try to help troubleshoot and fix the problem.