Let's start with the "Oops" problem. This has been linked to the "zero round trip resumption" feature. It is intended to speed up website connections, but there seems to be some kind of compatibility issue with Google sites. Currently, there is only a hidden way to disable this and see whether it helps:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(2) In the search box in the page, type or paste security.tls.enable_0rtt_data and pause while the list is filtered

(3) Double-click the preference to switch the value from true to false

After that, try Google again. Any improvement?

Unfortunately, it did not improve things.

I am starting to wonder if something might be up with my network connection on the new machine.

If it affects all browsers, then the network connection definitely would be suspect. Three other thoughts:

(1) Disable Firefox from using any proxy server settings it may be finding at the system level:

Open the Settings page using either:

• "3-bar" menu button (or Tools menu) > Settings (previously "Options")
• type or paste about:preferences into the address bar and press Enter to load it

In the very tiny search box at the top of the page, type proxy and Firefox should filter to the "Network Settings" section.

Click the Settings button, select "No Proxy" near the top of the dialog, and click OK near the bottom of the dialog.

Any difference?

(2) Try relaxing cookie protection on sites where you have login challenges:

Firefox recently rolled out "Total Cookie Protection" to more users. This limits how sites can use "third party" or "cross-site" cookies, meaning cookies from different websites than the one you see in the address bar. Some sites pass you back and forth between different servers during login because they have their services spread out over a number of different servers. In those cases, you might be able to submit a form successfully on one page and then the next page says you are not logged in. Frustrating!

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). More info in the following articles:

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

Any difference?

(3) Having to repeat two-factor authentication can indicate a cookie retention problem

If you have Firefox set to clear history/cookies when it closes, you may need to create exceptions for sites where you want to avoid repeating 2FA. If exceptions do not work, make sure you are not using private/incognito windows.

If it affects all browsers, then the network connection definitely would be suspect. Three other thoughts: (1) Disable Firefox from using any proxy server settings it may be finding at the system level: Open the Settings page using either:

• "3-bar" menu button (or Tools menu) > Settings (previously "Options")
• type or paste about:preferences into the address bar and press Enter to load it

In the very tiny search box at the top of the page, type proxy and Firefox should filter to the "Network Settings" section. Click the Settings button, select "No Proxy" near the top of the dialog, and click OK near the bottom of the dialog. Any difference? Sadly, no difference. Though things in Gmail worked a little smoother. One email I could not even read or view was visible again. It consisted of just three attached images from my phone. The virus scanner in Gmail has also frequently been unable to scan them for stuff. I have yet to try the following. Partially due to it not being a straightforward task or list of things to do, or your nicely laid out steps. I will give them another go after I have dinner. I think I mostly need to figure out what sites I need to create exceptions for. I am currently using a "Enhanced Tracking Protection" set to standard. I currently have no exceptions and would need to create some. I am worried about losing what access I have to now to my accounts by changing things. Having to log in to the websites that use various forms of 2FA was a very unpleasant experience. At least one login notification went to three different devices, in two different rooms, and on a good number of different accounts. .... (2) Try relaxing cookie protection on sites where you have login challenges: Firefox recently rolled out "Total Cookie Protection" to more users. This limits how sites can use "third party" or "cross-site" cookies, meaning cookies from different websites than the one you see in the address bar. Some sites pass you back and forth between different servers during login because they have their services spread out over a number of different servers. In those cases, you might be able to submit a form successfully on one page and then the next page says you are not logged in. Frustrating! 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). More info in the following articles:

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

Any difference? (3) Having to repeat two-factor authentication can indicate a cookie retention problem If you have Firefox set to clear history/cookies when it closes, you may need to create exceptions for sites where you want to avoid repeating 2FA. If exceptions do not work, make sure you are not using private/incognito windows.

If you're unable to send emails with Gmail, you can try the following troubleshooting steps:

Check your internet connection: Ensure that you have a stable internet connection. If your connection is intermittent or weak, it may affect your ability to send emails.

Verify recipient's email address: Double-check the email address of the recipient to ensure it is entered correctly. Even a small typo can prevent the email from being sent.

Check email size and attachments: Gmail has limitations on the size of emails and attachments. Make sure your email, including any attachments, is within the allowable limits. If necessary, try sending the email without attachments to see if that resolves the issue.

Disable browser extensions: Browser extensions or add-ons can sometimes interfere with Gmail's functionality. Temporarily disable any extensions you have installed and try sending the email again.

Try a different browser or device: If the issue persists, try accessing Gmail through a different browser or device. This will help determine if the problem is specific to the browser or device you're currently using.

Clear browser cache and cookies: Clearing your browser's cache and cookies can help resolve temporary issues. Go to your browser's settings, find the option to clear browsing data, and select the cache and cookies to clear. After doing so, restart your browser and try sending the email again.

Disable antivirus or firewall temporarily: In some cases, antivirus software or firewall settings may block the outgoing email. Temporarily disable them and try sending the email again to see if it goes through. If it does, adjust the settings of your security software to allow Gmail.

Greetings, Peter

Thanks for all of the help so far. I have been trying things and making some progress. A number of suggestions have helped.

Right now I think that the issue may lie somewhere with my network connection. Or a stray browser setting. I am not totally sure how to troubleshoot it effectively.