I already tried clearing my computer's cache and deleting all cookies from RenWeb.

Did you try t open the links by pasting them in the Firefox location bar?

What kind of links are that?
Are that links to the RenWeb website or the domain of this school or to other websites?

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

• Do NOT click the Reset button on the Safe Mode start window.

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

See also:

• http://kb.mozillazine.org/Error_loading_websites

They will not open when I copy and paste them into Firefox. Here is one of the links:

https://cca.client.renweb.com/ftp/CCA/Email/1202684/Speech%20Meet%20Letter%20with%20password%20and%20dates%2013-14.pdf

I will try the Safe Mode

In Safe Mode the link would still not load when I pasted it in.

When I reset Firefox, the problem was still there as well.

I am near the end of my trouble-shooting understanding :-)

Thank you for the help!

Those are PDF files.
The built-in Firefox PDF Viewer doesn't always handle all PDF documents correctly, so it is possible that this is happening in your case.
So you can consider to open them in PDF reader program (Preview or Adobe Reader) in case those program accepts internet based URLs.

See also:

• https://support.mozilla.org/kb/view-pdf-files-firefox-without-downloading-them

Thank you! I changed the default to opening them in Adobe Reader and it works like a charm! I so appreciate your help in solving this problem!

You're welcome.