Mail arrives, but late.
COMMON CAUSES
Greylisting. Many receiving servers temporarily reject mail from unfamiliar senders and accept it on retry. This adds minutes to the first message from a new correspondent and then stops. Large attachments taking time to transfer. A full mailbox at either end causing retries. The sending server queuing because of its own limits or reputation. Your mail client set to check infrequently. Check the sync interval before blaming the server.
CHECKING WHERE THE DELAY IS
Open the message and view its headers. Each server that handled it adds a line with a timestamp. Comparing them shows where the time was spent, and it is frequently not with us.
WHEN IT IS WORTH A TICKET
Consistent delays of hours affecting all mail, rather than one message Delays that started suddenly and affect everyone on the account
Include the headers of a delayed message. They contain the answer more often than not.
