Here's my guess: your host has you sign in on a different server than your cPanel, and your credentials are not carrying over. This can be caused by Firefox's "Total Cookie Protection" feature, which limits how sites can use "third party" or "cross-site" cookies. You can make exceptions to this feature when needed (for each server that you visit as part of the process of using this company's services). Try clicking the shield icon at the left end of the address bar (next to the lock). On the drop-down, click the blue slider switch to disable protection. Repeat on the site's other servers as you encounter them.

More info in the following articles:

• Introducing Total Cookie Protection in Standard Mode
• Total Cookie Protection and website breakage FAQ

Any difference?

Thanks. It did not solve the problem. There was no difference.

Does the page present an error message when you try to sign in? What feedback is it giving you or where in the process is it going wrong?

Simply, as stated: I login using the correct password. A page appears that says "Welcome back, Glenn." I then scroll down to click on the "open cPanel" button. Then a login window opens up. Again, I can log in.......and repeat the process.

So I think what would be expected is that the main page passes credentials to cPanel to sign you in automatically. Other than cookie restrictions, which should be resolved by disabling Tracking Protection, I can't think of any setting that would cause the problem. Do you use any add-ons which might restrict the data sent to sites? The typical method to rule out add-on issues is to restart Firefox in its Troubleshoot Mode. For more information on that option, see: Use Troubleshoot Mode in Firefox.

In troubleshoot mode, I was able to log into my website account. In Firefox Preferences, I unchecked boxes: use recommended performance settings, and use hardware acceleration when available. I Quit Firefox. I restarted Firefox. The problem persists. I rechecked the box use recommended performance settings. I quit Firefox. I restarted Firefox. I enabled the default Firefox theme. I tested connecting to my website account. The problem persists. In Firefox extensions, I unchecked Dark Reader because I recalled that it was about the time that I enabled that that the problem occurred. Thank you, jscher2000

I wonder whether Dark Reader was hiding some critical element of the page? It doesn't normally break things.