Hi @Dillon Gresham , welcome to Q&A forum!
Are you using SharePoint Online or Server? Have you installed third party software or windows update recently? Per my knowledge, usually we only need accounts and passwords to login. Is this issue with all sites and accounts?
Or screenshots can help us better understand the situation.
If SharePoint Designer is experiencing connection issues to SharePoint sites(when you are using SPO), try the following common solutions.
1.Clear the local cache files:
Close SharePoint Designer 2013.
On the local computer, remove all files found in each of the following folders.
- %APPDATA%\Microsoft\Web Server Extensions\Cache
- %APPDATA%\Microsoft\SharePoint Designer\ProxyAssemblyCache
Open SharePoint Designer 2013 and enter the account again to see if it works.
3.Administrators will need to Allow Custom Script in the SharePoint Admin Center settings to allow the SharePoint Designer connection. See Allow or prevent custom script for more information.
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