I have two Exchange 2013 servers: mailbox server "EXMAIL" and CAS server "EXGATE".
Recently, mobile clients have problems connecting to our mail Exchange server from smartphones. Sometimes a news users connects to our server from"Outlook
for Android or iOS" with the 20-50th attempt or can not connect .
In the CAS logs of the Exgate server, I found the following errors:
"[Eas] The number of outstanding proxy requests for mailbox server exmail.<domain> has exceeded the max limit 5000. Current request will be rejected."
Maybe this error is the cause of the problems?How to fix this error?
PS:From the Outlook for Windows and from Web Access (OWA) mail works without problems.