Email problems can come from DNS, mailbox settings, passwords, storage, spam filtering, or provider outages. Start with the basics.
Check Webmail
If webmail works, the mailbox is probably active and the problem may be with the device or mail client.
Check DNS
Confirm MX records still point to the correct provider. If nameservers recently changed, old mail records may have been missed.
Check Passwords and Storage
Expired passwords, full mailboxes, and incorrect server settings can all stop mail clients from syncing.
Check Sending Separately
Receiving and sending use different settings. SMTP problems can exist even when incoming mail works.
When asking for help, include the address, device or mail client, error message, and whether webmail works.
Define the Failure Precisely
Test sending and receiving with one external address and note the exact time. Establish whether one mailbox, one domain or every user is affected. Copy the complete error or bounce message without publishing passwords. “Email is down” gives support far less to work with than a repeatable test and timestamp.
Separate Mailbox and Device Problems
Sign in to webmail from a private browser window. If webmail works, compare the mail client's incoming and outgoing server names, ports, encryption and username with the provider's settings. Remove and recreate an account only after recording local folders, because some devices store unsynchronised mail locally.
Check Capacity and Authentication
A full mailbox may reject new messages while still allowing login. Clear unnecessary mail or raise the quota, then empty deleted items if they count towards storage. If a password changed, update every phone, computer and application using it; repeated attempts with an old password can trigger a temporary security block.
Check DNS After Any Domain Change
Query the live MX records and compare them with the intended mail provider. If nameservers moved, restore SPF, DKIM, DMARC, autodiscovery and verification records as well as MX. DNS propagation can create inconsistent results, so test through more than one resolver and avoid making repeated speculative changes.
Investigate Delivery Rather Than Connectivity
If messages send but do not arrive, check spam, quarantine and the sender's bounce. Confirm the sending domain passes SPF and DKIM and that DMARC policy is appropriate. A successful SMTP submission proves the server accepted a message, not that the recipient placed it in the inbox.
Escalate with Useful Evidence
Provide the affected address, sender, recipient, timestamp with time zone, message subject, error and whether webmail succeeds. Say what changed before the problem began. Support should not need your password; use a secure account-verification process instead.
