Not receiving some expected emails; Checklist
Someone has sent me a message but it still hasn't arrived. The sender has already sent it to me again but it still doesn't arrive either. I do receive other new messages from others though.
How do I troubleshoot this?
This is quite a generic request which could have a complex background but there are some easy things you could try and check without needing to contact your ISP or email administrator.
If you still can’t receive the message after performing the tests below, then it is quite likely that there is something wrong at mail server level. In that case you or the sender should contact the mail administrator or ISP. Tell them the results of these tests and they should be able to trace the in- or outgoing message and see where exactly it gets dropped.
Check Junk E-mail folder
This one might be obvious but can be easily overlooked;
Did the message perhaps end up in your Junk E-mail folder?
Search for messages received Today
If you have rules configured to sort your mail automatically, it could be that the message has been moved to another folder or even been deleted.
Check your subfolders or do a search for messages that have been received today or disable all your rules and have the sender send it to you again.
A good way to keep up with new messages when using rules to move them is by using a “Today’s Unread Mail” Search folder.
Check virus scanner or 3rd party anti-spam tools
If you are using a virus scanner which integrates with Outlook or acts as a “mail proxy” via a special mail module to scan your message before delivery, you should disable or uninstall this component of your installed security suite and see if the message arrives now.
Disabling your virus scanner completely will usually not help you with this and would put you at risk; only disable the mail module, which is safe to do. For more info see; Disable virus scanner integration?
If you also have a 3rd party anti-spam tool installed, disable this as well and/or see if it holds the message in quarantine somewhere. This could be somewhere within the tool itself or in a separate folder in Outlook. See the documentation of your anti-spam application to find out what it does exactly when it classifies a message as spam and how to disable its Outlook integration.
Collecting your mail on multiple computers or a mobile phone
If you have your mailbox configured on multiple computers or mobile devices (laptop, tablet, mobile phone, etc…), check if the message has arrived on any of those computers. If so, it could indicate an issue with your current Outlook configuration only and a new mail profile might help.
If you are using a POP3 account, make sure you have configured all your devices to leave a copy on the server so that each device can collect all mail.
Check your web based mailbox
At this point we have determined that the message is not in your mailbox on your computer (or in a mailbox on another device) and that it doesn’t appear to be blocked by a local application or configuration. Now it is time to check your web mailbox.
Your web mailbox is how you would access your mailbox via an Internet browser. In general each ISP offers this method as well. If you are using an Exchange account, this would be called OWA which stands for; “Outlook Web Access” or “Outlook Web Application”. You can ask your ISP or mail administrator if you do not know the correct web address (URL) for it.
Anyway, once logged on, see if the message shows up in the web based mailbox. If you are using POP3 and do not have the option configured to leave a copy on the server, you’ll have to do so now and ask the sender if he/she can resend the messages. If it arrives in the web based mailbox, this could indicate a sync issue or a corruption in your mail profile.
In addition, check if the web based mailbox also offers Junk E-mail functionality. If so, it could be that the message has been filtered out at server level already and thus Outlook couldn’t have downloaded it. Check if you can fully disable this server level filtering.
With POP3, it could also be that the message got moved to another folder on the server. As a POP3 account can only download from the main Inbox folder, Outlook will never see the message if it got moved. Move the message back to the Inbox and Outlook should be able to download it now.
Have the sender check the Outbox
The message could still be stuck in the sender’s Outbox. Common causes are that the message is too large to be sent, an outgoing virus scanner is in the way or that there is something wrong with his/her outgoing mail server.
Request the sender empty the Outbox and try to send the message again (without attachment first) and see if it leaves the Outbox now. If not, the sender should check for send/receive errors.
Have the sender send to another address
Request the sender to try to send a Plain Text message with just a few words to somebody else or to another address of yours and if that works, have the sender send that same message to you.
If it doesn’t arrive for you but it does for the other address, then the message could have bounced (or something more complex is going on at mail server level).
Have the sender check for bounce messages
Bounce messages are return messages to the original sender receives when a message could not have been delivered. They are also known as NDR messages; Non Delivery Receipts. Usually these messages contain some additional information why the message wasn’t delivered. Common causes are;
- Mailbox full
The recipient should clean his/her (web based) mailbox!
- Wrong e-mail address was used
The sender might want to delete this address from your address cache.
- The sender needs to enable authentication for the SMTP server.
- Sending mail server is on a black list or otherwise rejected to send to this server
The sender should contact his/her ISP or mail administrator.
- Message is delayed
This means that currently no route was found between the 2 mail servers. This could indicate a network issue, a DNS/MX configuration issue or that the sender has made a spelling mistake in the domain name part of the email address (after the @ part of the address).
This NDR message could have arrived in the Junk E-mail folder or even in the Deleted Items folder of the sender as some people have created a rule for this (usually this rule has been created when they received a lot of bounce messages when a spam run sent a lot of emails out with their email address as the sender).
Contact your ISP or mail administrator
If none of the above helped, and you still can’t receive messages from this specific sender, as said before; you should contact your mail administrator or ISP for further testing and analysis of the issue at server level for you.