Sometimes a simple reboot of the system hosting the JIM will suffice, and restore communication; that is what I would try first. Failing that, you may need to reinstall the Infrastructure Manager on the server. I believe I saw a thread not too long ago stating that a certificate may have expired, and the user needed to reinstall the JIM, per direction from Jamf.

@RBaZ I'd echo @Jason33 's suggestion of restarting your JIM instance, but if that doesn't work re-install shouldn't be necessary as just re-running the enroll command should re-generate the certificate used to secure communications.

I have this same error on our JIM, despite the fact that lookups continue to work. I pointed this out to a Jamf engineer I've been working with, and he has no idea how that can be the case. I haven't rebooted the system running JIM yet, but I'm going to do that to see if the error clears up, at least temporarily.

Hello,

Thanks for the answers
We found the problem
The connection with the LDAP server was broken (we tested the connection on JAMF Pro)
It was a VMWare update on our server that had disconnected a virtual card

Now we can reach the LDAP server and the message has disappeared
Problem solved! 👍

Curious if you ever were told a solve on this? Our org is in a similar situation.