Troubleshooting

Find answers and help to common problems

Cannot login to Mail Portal (Authentication error)

• Re-check your login credentials.

• Check if the account is enabled. From Mail Portal, Mail > Accounts > Enabled (status) and Mail > Accounts > API access (status). Both parameters must be toggled ON (yes) for login to Mail Portal. Enabled parameter controls API/GUI access and if applicable, email send/receive access. API access parameter controls API and subsequently GUI access (as GUI is built on top of the API).

Mail Portal (Invalid authorization error)

• Logout and log back in. This error might be caused if you access the same account from a different browser/device as the existing session is invalidated upon logging in each time.

Cannot access webmail (roundcube) (Authentication error)

• Check if the MailUser is enabled. From Mail Portal, Mail > Accounts > Enabled (status)

• If 2FA enabled for your mail user, please set device password and use device password for webmail/roundcube login.

Cannot access webmail (other errors)

Webmail errors might happen immediately after service unsuspension producing errors like Connection to storage server failed. To recover from these errors follow the steps below.

• Logout and log back in.

• Clear browser cookies and cache.

• Contact our support, if you above steps do not solve your issue.

Mail Users (email accounts) are automatically disabled

• If you send spam/mass mail our system disable the email account. 2FA is mandatory for MailUsers (email accounts) to reactive your account. The system disables a MailUser if 2FA is disabled for 3 consecutive days. This is to prevent compromised user spamming incidents that would affect your server’s IP reputation and deliverability as there are no sending limits without Premium relay.

Cannot connect to mailserver

• Please contact our support if you face this issue.

Cannot receive email

• Check if the MX record for your domain is configured and propagated. DNS records may take up to 24-48 hours to propagate around the world. Verify DNS settings by sending an email to [e-mail] to get back a diagnostics report.

• Login to the email account (using either webmail or any email client) at least once before sending emails to it.

• Make sure the account is not configured with POP on any other email client, webmail and multi-device access will only work with IMAP.

• Make sure the account does not have any forwards/redirects setup.

• If the domain is sending from an external service/server, make sure the sender is not blacklisted and/or failing message authentication mechanisms like SPF, DKIM, and DMARC.

• Make sure the MailUser (email account) has enough storage quota left to receive the incoming email.

Cannot send email

• Check if the MailUser (email account) is blocked from sending due to abusive activity by logging in to Mail Portal as MailUser or if you’re a DomainAdmin from Mail Portal > Stats > Blocked senders.

• Check your mailbox and sending quota. See more info on sending limits in FAQ Section.

• Update password and enable 2FA for the account as compromised passwords can cause MailUser accounts to be over quota even if user didn’t send many mails themselves.

• Check for any misbehaving mail client program(s) that may be repeatedly trying to send mails queued in its outbox. This behavior would cause the MailUser’s sending quota to be perpetually exhausted.

• Make sure your domain has proper SPF, DKIM & DMARC records configured and propagated. DNS records may take up to 24-48 hours to propagate around the world. Verify DNS settings by sending an email to [e-mail] to get back a diagnostics report.

• If the message is not rejected during the SMTP transaction, but is bounced with the error Your domain's TLD is blacklisted from sending through this relay it means your domain’s TLD (e.g., .icu) is blacklisted due to high rate of abuse, likely owing to its low registration cost which is abused by spammers. Please contact support for whitelisting your domain from this check.

• If the message is not rejected during the SMTP transaction, but is bounced with the error Sender email or domain is blacklisted from sending through this relay it means there were instances of deliberate spamming verified by a human operator that needs your attention by contacting support. This error would never be produced in cases of compromised user spamming incidents as these are handled automatically by the system and requires no intervention other than by the affected MailUser (to update password and enable 2FA).

Sent email not found in recipient’s inbox (emails going to spam folder)

• Make sure your domain has proper SPF, DKIM & DMARC records configured and propagated. DNS records may take up to 24-48 hours to propagate around the world. Verify DNS settings by sending an email to [e-mail] to get back a diagnostics report.

• Check recipient’s spam folder. Mark email as “Not spam” to train filter and add the sender to recipient’s address book. If the domain/IP is brand-new or does not have an established sending reputation it may take a few (2-4) weeks for it to build one.

• Make sure the email that you sent was not spammy, blank/test/placeholder messages may be blocked by our outbound filters (Premium relay). Use spamcheck.postmarkapp.com to check the spammyness of your emails.

• Always send emails with real content, do not send blank/test/placeholder emails especially from a new IP/domain. Let your reputation build organically and in 2-4 weeks emails will be delivered to inbox.

Error 550. Recipient address rejected: undeliverable address (User doesn’t exist)

• Login to the email account (using either webmail or any email client) at least once before sending emails to it. Additionally, check if the MX record for your domain is configured and propagated. The DSN (bounce message) should contain information on which server responded with the 550 reject.

• If the address exists, please wait up to 1 hour for any negative caching to expire.

• This error can be caused when your hosted domain is same as your mailserver hostname. For example, if your hosted domain is project.yourdomain.com and your mailserver hostname is also project.yourdomain.com, then sending emails to [e-mail] will cause this error. If you’re reading this, chances are you’ve already provisioned a mailserver with hostname matching the domain/subdomain you want to host. While it is not recommended to do so, we do have a workaround for you that involves changing a few server configurations. Contact support for help with this.

Webmail: emails not displaying after logging in

• This error maybe caused after a large migration or data transfer. Please login to the account from an IMAP email client like Outlook or Mac Mail on your desktop and let the inbox and folders index(sync). This can take a while depending on the size of your inbox and once the indexing has completed in the client you can start using the webmail normally. With Cloud/Dedicated servers, it is possible to rebuild indexes for all users from Server > Actions > Dovecot index rebuild

Spam filter: false positives (legitimate mails going to spam folder)

• Move message to Inbox or any folder other than Trash to train the spam filter that the message is not spam.

• Increase domain’s spam thresholds from Mail > Domains > Antispam thresholds. Default spam threshold score is 6. This is the spam score at which emails are flagged and sent to junk folder. Experiment by increasing threshold to higher values for each domain.

• In some rare cases, mails maybe detected as spam due to sender misconfiguration. Inspect the headers of the mail to see which spam rules were triggered, contact support for help with this.

• Whitelist sender domain, email, or IP/CIDR from Mail > Domains > Antispam WL / BL.

Caution

Whitelisting would allow spoofed messages purporting to be from that domain or email address through, use with extreme caution. It’s recommended to whitelist trusted IPs/CIDRs instead of domains.

Spam filter: false negatives (spam mails in inbox)

• Move message to Junk folder to train the spam filter that the message is spam.

• Blacklist sender domain, email, or IP/CIDR from Mail > Domains > Antispam WL / BL.

• MasterAdmins can blacklist sender domains, emails, or IPs/CIDRs from Mail > Settings > Global whitelist and blacklist.

Deleted my data (recover my data)

ExonHost keeps rolling snapshots of email data for last 30 days as standard for all our hosted email plans. You can contact our support if you need to restore your data.

Timeouts or intermittent service issues

This is most probably caused due to server overload. Please contact our support if you face timeout issue.