MSExchangeIS\Active User Count
would probably be best for unique users count.
A good description and differences of other useful counters can be found at http://blogs.technet.com/b/exchange/archive/2006/09/11/3394858.aspx
Besides backup, any IT division should have a disaster recovery plan. You will find a few tips below relating to the development of such a plan and to what issues one should pay special attention in the course of backup planning.
To add imagery to an HTML email signature, you have two options available to you. You can either add a logo/image by embedding it directly into the signature or hosting it externally and linking to it.
The vast majority of email clients display l…