Chapter 8 · 1B Mail guide
Troubleshooting: common problems and their solutions
Most problems come from the provider's security settings or the network. Find the message you see below; the texts in bold are the ones in the app.
Keep 1B Mail up to date
On the computer, 1B Mail checks once a day (Check for updates automatically) for a small file signed by 1Byte Systems, and Restart to update installs the new version. To check now, open Settings › Updates › Check for updates. The Flatpak and Microsoft Store versions update through your software center. On Android, updates come from Google Play.
The log
If we ask you for the log, you'll find it at %LOCALAPPDATA%\1Byte Systems\1B Mail\v3\1bmail.log on Windows and ~/.local/share/1bmail/v3/1bmail.log on Linux. It never contains passwords.
Problems and solutions
“Google didn’t accept the app password”
Google asks for an app password when you don't sign in with Google: turn on 2-Step Verification in your Google account, open “App passwords”, create one called “1B Mail” and paste the 16 letters. If you changed your Google password, older app passwords stop working: create a new one. Signing in with Sign in with Google avoids app passwords altogether.
Yahoo, iCloud or AOL reject my password
They need an app password instead of your normal one. Yahoo: Account security › Generate app password. iCloud: account.apple.com › Sign-In and Security › App-Specific Passwords. Paste it in App password.
“Your organization needs to approve 1B Mail”
Your Microsoft 365 administrator only lets approved apps read email. Click Copy link for the administrator (on Android, Share the link) and send it to your IT department. Once they approve 1B Mail, everyone in your organization can sign in: come back and click Continue with Microsoft again.
Microsoft accepted the sign-in but IMAP is turned off
Your organization has turned off IMAP (or Authenticated SMTP, to send) for your mailbox, so only Outlook can open it. Use Copy a request for your IT department (on Android, Send to your IT department) to ask them to turn it on.
Outlook.com: “its mail server didn’t let 1B Mail in yet”
Open outlook.com in your browser once (Microsoft sometimes asks you to confirm something there) and try again.
“The server rejected the username or password”
Check the address and the password. Many providers need IMAP turned on in their settings, or an app password. To change the password of an existing account, use Sign in again in Settings › Accounts.
The phone can't connect to the computer
Both must be on the same Wi-Fi (guest networks and mobile data keep devices apart). On Windows, allow 1B Mail in the firewall and choose “Private networks”. Turn off the VPN on the phone or the computer for a moment: a VPN keeps the phone from reaching the computer. If nothing works, use With a file instead.
“The server's certificate isn't trusted”
This happens with self-hosted servers, but it can also mean someone is intercepting the connection. Compare the SHA-256 fingerprint with the one your provider gives you and only then click Trust this certificate.
“Some accounts no longer get new mail on their server”
The domain moved to another provider, so the old server no longer receives your mail. Click Change servers and type the new provider's settings; 1B Mail tests them before saving.
New mail doesn't arrive on Android
Turn on Instant mail in Settings › Sync and battery, and in Battery optimization let 1B Mail run in the background. Data Saver also pauses background checks on mobile data.
Proton Mail can't be added
On the computer, open Proton Mail Bridge, make sure you're signed in and use its Bridge password. On a phone, Proton only allows its own app, so 1B Mail on Android can't add Proton Mail.
For 1B Mail 0.3.14 on Windows and Linux and 0.2.9 on Android.