Exchange 2013 Weird OWA behaviour

[steele_uk]

Just moved over from Exchange 2007 to 2013 and everything seemed to run smoothly but...

 

When trying to access through OWA, occasionally i cannot connect - timeouts.

 

When i can connect, i the compose a mail but it sometimes (often) fails with a message "The mesage cant be sent because your device isn't connect to the internet"

 

When i do connect, there is a time when i cannot read emails, as if i have been disconnected.

 

It almost seems like the service is toggling on and off, but my connection to the internet stays constant.

 

I am thinking the firewall is dropping the connection, but just wanted to know if anyone had come across anything similar.

 

We never had this problem with Exchange 2007, but 2013 is a very different beast.

[kmount]

Have you ruled out the firewall by testing internally?

[steele_uk]

I have used OWA internally, without a hitch, but not extensively. I will try a days work using only OWA tomorrow.

 

thanks,

[steele_uk]

Still no further on. I have seen logs on the firewall that suggest some requests from my home IP are successful, - I connect and the firewall describes the connection as Web based mail on SSL, minutes later I try and fail to connect, and the firewall reports the connection as "incomplete".

 

I have raised with our firewall support engineers who are puzzled, but asked whether we use NLB on Exchange 2013, which we do.

 

I am starting to think I need to investigate this. Does anyone know of any links to health check whether NLB is working and configured correctly?

 

Do you think this could be the cause?

 

Thanks,