Mac Mail: G-Mail Spam no longer appearing

Thank you... safe boot appears to have corrected the problem; the junk mail didn't show in the regular boot, but did show up when I tried safe boot. I had tried "Rebuild" yesterday, but had no change in how the mailbox worked.

Sadly, no... the next time I logged into check mail, the G-Mail account again showed how many messages were there, but didn't display the messages in the "Side Preview" column. I booted again in safe mode, the messages then appeared; I shut down and then rebooted normally and the messages were still visible. I deleted them. This morning it was back to not showing the messages (although next to the mailbox it says there are 45 messages).

This particular G-Mail account is one I don't use much, except as a backup mailbox in case I can't be reached through my primary account. It was a "learning experience" from many years ago, where I used first and middle initial and my last name. Every robot seems to find this combination, and everyone with the same initials and last name tries to get this account, probably has to attach a number to it, then forgets what their address is and uses mine to sign up for shady website deals... and I've been getting the spam ever since.

The regular e-mails download into the incoming box just fine, it's only the garbage (often 30 to 100 per day) that gets sent to the "Junk" box.

I've downloaded EtreCheck, but Pastebin is confusing me at the moment. I'll try to figure it out in a couple of days. Would Dropbox work as an alternative, if I don't figure out how to use Pastebin?

Apple keeps deleting my posts with the dropbox URL... but the good news is that since deleting AVG, the posts seem to show up every time. Thanks for your help!