If you are using BitDefender as your antivirus, try the following:
1. Open BitDefender
2. Click the little gear icon at the top of the window
3. In the list that appears, click “Exclusions”
4. Click the “Add Exclusion” button
5. Click the radio button next to “Add URL” and enter “proxy.campbell.edu”
6. Click the “ADD“ button
7. Click the “Cancel” button
8. Close BitDefender
9. Try and access the library proxy again