Exchange 2010 Abnormal Bandwidth Usage

[Sik]

Hello all,

I manage an exchange server for a client and have been maintaining this server for over a year, about 6 months ago I moved the server from a 2003 SBS to a 2011 SBS with exchange 2010. All was running well for four months, however, the client complained last month that their data limit was being reached very quickly.
I logged into the server and found no problems, after checking their Cpanel I noticed that the bandwidth usage has been climbing over the last two months.

Pop3 connections have gone from an average of 1.1Gig per month to 4.2Gig last month and 4.9Gig so far this month.
there are only 11 users using this exchange server in the domain! I am using the built in Pop3 connector and it is scheduled to retrieve mail every 30 minutes.

I have monitored the amount of mail and there have been no changes in volume for a few months.

Anyone have any ideas as to why the usage is climbing like this?

 

[PsyWulf]

Data limit?
On the website for Pop3 or on the DSL/whathaveyou for Exchange?

 

[Sik]

Oh sorry, the limit for both the local service provider and the website.

I have installed ntop on the ClearOS gateway to make sure it is the Exchange using the data and not a tunneling service - ntop reports the same usage as the website Cpanel.

 

[PsyWulf]

RUnning Activesync? I've seen mobile devices try to check for mail every minute racking up quite a bill

 

[Sik]

Thank you PsyWulf,

It was running Activesync, I have just disabled it through IIS by stopping MSExchangeSyncAppPool.
Will that permanently disable Activesync?

 

[PsyWulf]

The app pools will restart after every server restart or when requested,but it's a good test for now to see if it's mobiles that are chowing data,they wont get activesync mail on their devices though

 

[Sik]

Thanks allot for the help, will monitor it and report back