Why do messages appear in Spam?
Spam filtering is done by Gmail’s servers. Mimestream does not have any spam filtering logic, and is not involved in determining what messages are spam. Mimestream syncs the contents of your account to faithfully mirror what is shown in the Gmail web interface.
What happens when marking a message as “Not Spam”?
Mimestream removes the Spam label and adds back the Inbox label. These modifications are communicated back to Gmail via the Gmail API.
We do not have insights into Gmail’s backend spam filtering to provide any guidance on how (or if) these actions impact future spam filtering.
How can messages be prevented from being marked as Spam?
First, consult the official Mark or unmark Spam in Gmail support article for the best ways to handle Spam issues within your account.
To prevent messages from a specific sender from getting marked as Spam, try using the Gmail web interface to add that address to Google Contacts:
- Hover over the From address in the message’s header.
- In the card that appears, click the “Add to Contacts” button.
Another option is to try using the Gmail web interface to mark these messages as “Not Spam” (instead of performing the same action within Mimestream). We don’t have any clear knowledge about how Gmail’s spam filtering feedback works, but it’s certainly possible that Gmail may weight feedback from the web interface more heavily.
Why does it seem like I’m getting more Spam since I started to use Mimestream?
Gmail’s Spam filtering is extremely good, but does have occasional false positives (like any email service). Therefore, it’s a good idea to routinely check Spam.
By default, the Gmail web interface shows Spam hidden in the “More” section. Seeing Spam in the primary label list, above the “More” section, requires deliberately changing an account’s initial settings. With Spam hidden under “More” by default, it is out of sight and easy to forget about about checking.
In contrast, Mimestream makes Spam a top-level sidebar item for all users, and shows a badge count. This UI design steers users towards checking Spam regularly. For some users, this is the first time that they are routinely checking Spam, and the first time they are noticing false positives.
To re-iterate, Mimestream is not involved in determining which messages are Spam.