Gmail telling me I have 2 new emails when I have only one

Since yesterday or so, Gmail has had this strange glitch whereby it will tell me that I have 2 new emails when I have only one. This has happened multiple times. Is the system double-counting emails?

Could be that some of your new emails are being automatically moved to the Spam or Junk folder. (I don’t remember which term they use). But check in there and could be you’ll see a bunch of un-opened emails.

On rare occasions I’ve had emails I did want to see automatically moved to Junk/Spam.

Yahoo! mail sent me over 600 emails in one day last week. They were things with dates back to July 31.

What happens is that I will click on the one new email, and the (2) notification automatically vanishes. It’s like one email counts for two.
Hope not some sort of infected inbox?

What exactly are you referring to? Notification on Android? Tab title in a Windows browser? The number next to “Inbox” in the web interface? Something else?

Were these e-mails involving multiple people? If Mary sends you and Bob an e-mail saying “Where should we go for lunch on Friday?”, and then Bob replies-all and says “Let’s try that new Thai place”, Google will recognize that as being one conversation, and will group it all together in your inbox. You can click one place to read both (perhaps with some scrolling). But it’s two new messages.

The number next to Inbox. It would say “Inbox (2)” when in fact there was just one unread email only. Although now the problem, weirdly, seems to have resolved itself this afternoon.

You don’t think it was one conversation that had 2 new messages in it? E.g. if someone replied to you twice, or original message was sent to multiple people, and 2 people replied? Each line in the inbox is a conversation, it can have multiple message in it with the same subject.

Hypothesis A:

In addition to the automatic Spam folder, GMail has built-in options to sort your mail into bins such as “Ads” and “Social networks”; those messages then wouldn’t appear in your main Inbox. The “All messages” link can show you all messages at once (except for Spam); there may be 2 unread messages there.
Hypothesis B:

A GMail account looks like a solid set of files that are stored somewhere, but it’s actually stored in several places at once. If you’re looking at the same GMail account on your phone and on your PC, and you delete an e-mail on the phone, the PC may allow you to open and read that same message for a little while because it’s not necessarily the same server, in the same data center, that’s serving both screens. Most of the time it seems pretty seamless, but there’s a lot of code sending signals back and forth between servers to keep up an air of consistency and synchronicity.

If I do a search in my GMail for, say, “cucumber sandwich”, I will get a full page of results with a mention “1-50 of several hundred messages”; if I keep paging through the results it will eventually say “150-200 of 637 messages” but eventually when I get to the end of the list there will be 621 instead of 637. These are estimates because getting a precise count would involve too much signaling and synchronisation and would probably slow down the GMail experience. Few people care about a precise count on this, they just want all their CucumberSandwichFans.com newsletters to be there and every click to be responsive.

So your Inbox has accumulated 3 new messages overnight, you read one on your phone, a filtering process on a different server determines that another one of those messages is such obvious spam that it doesn’t even deserve to be in your spam folder. Now the count of unread messages should be down to 1 but those signals had slightly inconsistent time stamps and the count remains at 2. Most people won’t notice, they have over 700 unread messages these days anyway.