Hello Jayant,

Specifically what types of emails are not being sent and giving us this error? Are we doing a send email event in the workflow? Is it a notification for a user that they have a worklist item? Or an escalation email?

Additionally does this happen across all workflows? Or is it just a specific one. If only some email events on some workflows fail, we might want to check the design of the email event itself to see if that is the source of the issue.

To me this looks like exchange is not happy with what we are trying to send to it from the K2 end (workflow). Since the error is not so detailed I'd recommend seeing what exchange is saying on its end. I would start with the Message tracking logs first when this error is seen on K2. Get a timestamp and then check the logs on exchange at that same time. 

https://technet.microsoft.com/en-us/library/bb124375(v=exchg.150).aspx

There are also some additional logs that might clue us in on a more detailed error as well:

https://technet.microsoft.com/en-us/library/dd302434(v=exchg.150).aspx

Regards,

Evan

Hi there, 

The "ConnectionError" portion of the message seems to indicate that the error is happening when polling the K2 mailbox for replies. I've seen the internal server error when there's a sync issue between K2 and the exchange server. You can try restarting the K2 service if you haven't done so already, or if you have and it hasn't made a difference you might want to clear the SyncState stored in the MessageBus.EwsSyncState table in the database. (You would only want to clear the SyncState column, and make sure to make a database backup prior to making any modifications here)

For sending, are there any other errors in the logs?

Hello, 

Please see link below, hope this helps get you pointed in the right direction.

https://portal.k2.com/support/report/snapshotnew?id=146646

Kind Regards

Luyanda

Note: K2 will not accept any liability for any issues arising from actions taken in respect of the information provided by any forum member.

I finally fixed the issue. It turned that the Network team had migrated the email account. I had to rerun the K2 setup and point K2 to the correct email address.