Exchange mail Account hacked ?

My Company is using Exchange 2010 as it mail servers.  It appears the mail server is now hacked as  hackers are using  one the company's  valid email account on the exchange to send malicious mail/ messages to  our client.
How do I stop this ?
zuguluAsked:
Who is Participating?
 
Alan HardistyCo-OwnerCommented:
Change the password for the account immediately and then restart the Transport Service.

Then empty out any queues of invalid messages and review the security of your server settings / password settings as they sound like you have weak passwords and they aren't changed often enough.

Alan
0
 
Praveen Kumar BonalaProgrammer AnalystCommented:
Most probably there could be a misconfiguration in SMTP relay.
In a Small Business Server environment, you may have to prevent your Microsoft Exchange Server-based server from being used as an open relay SMTP server for unsolicited commercial e-mail messages, or spam. You may also have to clean up the Exchange server's SMTP queues to delete the unsolicited commercial e-mail messages. If your Exchange server is being used as an open SMTP relay.

Please check following link to configure SMTP Relay.
http://support.microsoft.com/kb/324958
0
 
Miguel Angel Perez MuñozCommented:
I suggest you force all users change his passwords and set a expiry policy.

To force all users (domain administrator too) you can run this from powershell:
import-module activedirectory
get-aduser -filter {objectclass -eq "user"} | set-aduser -ChangePasswordAtNextLogon $true
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.