Change New Exchange Server - Error pear_error: message="NO, Server Unavailable.

General discussion of Mantis.

Moderators: Developer, Contributor

Post Reply
NandoNaldo
Posts: 122
Joined: 09 Mar 2016, 21:44

Change New Exchange Server - Error pear_error: message="NO, Server Unavailable.

Post by NandoNaldo »

Hello,

We need to migrate from one exchange server to the other one. I have changed the IP of the new exchange server and the user used to logon but when i try to do complete test i have:

Mailbox: Email test pershkrim
Location: Attempt login
[pear_error: message="NO, Server Unavailable. 15" code=0 mode=return level=notice prefix="" info=""]

Please could you help me ?
TerranceM
Posts: 26
Joined: 27 Aug 2019, 13:55
Location: USA

Re: Change New Exchange Server - Error pear_error: message="NO, Server Unavailable.

Post by TerranceM »

I've come across this issue twice with 2 different exchange 2013 farms while setting up IMAP to use IMAPSync to migrate mail. The issue only happened when accessing 1 folder with lots of mail messages. A simple test is to use OpenSSL to verify the issue like:

openssl s_client -quiet -crlf -connect mail.domain.com:993
A01 login domain/user password
A02 LIST "" *
A03 SELECT "problem folder"

IMAP will return: A03 NO Server Unavailable. 15

After change lots of IMAP settings, the resolution is to enable IMAP protocol logging. It was previously (by default) disabled and this issue would happen. We disabled it again and the problem returned for the same mailbox. Re-enabled logging en voila works.

Set-ImapSettings -Server <server-name> -ProtocolLogEnabled $true

Hope this helps!

--
Terrance
Post Reply