Has anyone dealt with an issue where an SMTP server starts holding .eml files in the Queue folder for unpredictable amounts of time and then sends them all at once? This problem began for us yesterday, and everything seems to be in order – we haven't made any recent changes. We did switch ISPs about three weeks ago, but overall mail delivery has been fine. Our SMTP server is primarily used for scanning to email, alerts, notifications, and report deliveries. Occasionally, restarting the service clears the messages, but sometimes it doesn't do anything. The waiting time for messages to clear can vary from an hour to several hours. This has always functioned without a hitch, so I'm struggling to find reliable information on diagnosing this sudden behavior.
2 Answers
What mail software are you running, and is it hosted or on-prem? If it's an on-premise setup, particularly with something like Exchange, it might be experiencing back pressure. Again, double-checking your disk space is wise, just to be safe.
First, you might want to check your free disk space. If it’s running low, that could cause delays in processing. Also, have you looked at the message logs for any clues? Might help you understand the current queue status. It can be a good idea to monitor those as they can give you hints about what's happening behind the scenes.
Yeah, how much free space do you actually have on that drive?
I'm showing 25GB free on a 160GB virtual HDD, which should be enough for basic operations.
This is just the Windows SMTP server for us, and we don’t have Exchange installed.