I am using Windows 10 home edition on a desktop PC and my browser is Firefox, along with Avast Free Antivirus. All these programs are up to date with the latest versions and have been using them all with Gmail for close to two decades without ongoing issues.
Typically, I open a Firefox browser with multiple tabs, including my Gmail, Google Calendar and Google Search, and leave the browser open all day on my home PC. Gmail automatically refreshes to show new emails as they arrive under normal conditions. For the past week or so, I am finding that Gmail is giving a popup error message saying “Oops, the system encountered a problem, retrying in…” (see first screenshot). then I try to reload or refresh the page and it is unable to do so. I close out the tab and then try to open Gmail in a new tab and the page stalls out trying to load (see second screenshot). This happens multiple times throughout the day. The only way to get Gmail to load again is to close out the entire Firefox browser with all the tabs, relaunch Firefox and then restore previous session or start a new session opening a fresh Gmail tab.
I posted on Firefox forum and was told to try running Firefox in troubleshoot mode (disabling addons and extensions) and to clear cookies and cache for Gmail and Google sites. This didn’t fix it, although I found that opening a Firefox private window and logging in to Gmail again did fix the issue and I am able to leave the window open all day with Gmail refreshing periodically without system errors. One user on Firefox forum suggested disabling Avast to see if that fixed it. It did fix it. So this suggests something is happening where Avast is preventing Gmail page from refreshing.
Another related issue is that when this error happens in Firefox with Gmail, I cannot load a Google search page at all, the tab remains blank and in order to do so I must close out the browser window and start over or restore previous session.
Is this a bug in Avast? It’s been happening all day every day for about a week and is annoying me. I would see this issue crop up sporadically on rare occasions but it was usually due to a connectivity problem. When this happens in Gmail, all other sites will load and refresh normally, it’s only Gmail that gives me this error.