hello dnatch, here's an article that covers the most common solutions for the issue you've described: What to do if you can't download or save files

does anything in there help to address your problem?

Tried everything in the article. Nothing fixed it. Interestingly, I was able to download an exe file, but nothing else. I even re-installed Firefox. Guess I'll migrate to Chrome

Did you try Safe Mode?

• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test to see if that helps.