I have lost more than thirty minutes trying to solve a small but annoying problem. The solution is rather simple, but it may not be apparent at first. I hope this post can help others who have stumbled upon the same issue.
I have a low-traffic Gmail account I usually check on my Power Mac G4 Cube using Mail.app in Mac OS X 10.4.11. Since it’s low-traffic, I don’t check it very often. But today I felt that a check was long overdue, so I opened Mail, clicked the Get Mail button, and I was presented with the annoying dialog box I sometimes see when there’s a network problem, the password confirmation dialog box. It appears that the pop.gmail.com server rejected my account password, so I was prompted to insert it again. I did, repeatedly, but to no avail.
So I logged in via the Web interface — without any problem — and found a message from Google that told me Google prevented the sign-in because it is from “an app that doesn’t meet modern security standards.”
At first I thought Google had updated/changed the server ports for incoming/outgoing mail, and after tweaking a few settings (I had the outgoing server port still set to ’25’ instead of ‘465’), I tried again to download my email messages. No joy. I then tried to look for an answer in the Gmail support pages, but my frustration and annoyance prevented me from finding what I was looking for more promptly.
I was about to give up, when I noticed an error message in Mail from the Gmail server that thankfully contained the link I was searching, and access to Gmail from Mail.app under Mac OS X Tiger was restored. The essential page is this one: Allowing less secure apps to access your account. You have to make sure you reach this page after you have signed in the problematic account via the Web interface.
Look down the page until you find this bit:
Click on the “Less secure apps” section of MyAccount link and you’ll be taken to the Less secure apps page. Click the Turn on radio button to allow access for less secure apps. Now go back to Mail, check for new mail, and the messages should start downloading.
Again, I hope this helps. And I hope it’s clear that in so doing, you’re choosing to weaken the security of your Gmail account(s) in exchange for the convenience of accessing the account(s) from a vintage Mac with older software. In my case, it’s not an important or primary email account, I have been downloading mail on the Cube from that account for the past six years, and I wanted to continue to do so.