I'm looking for a monitoring tool for Exchange 2007 to keep an eye on queues, resources and services status Is there something completely free out there ? Thanks

You can use powershell to monitor Exchange and send you email alerts. This will take some time depending on the extent you want to go. Depends on what OS you are using, you can attach tasks to Event Viewr logs to trigger emails to you. Server 2008 will do this. Sukh

http://www.solarwinds.com/exchange_monitor/ Not sure what versions it supports. Note that you get what you pay for. I would suggest looking at affordable tools such as Servers Alive as well. You can try it for free. http://www.woodstone.nu/salive/ The problem with creating your own monitoring is that you dont know what you should be monitoring and you can not simply focus on event logs. More info: http://technet.microsoft.com/en-us/library/bb397229(EXCHG.80).aspx

Solarwinds is a good tool as Andy has instructed. check this too http://www.msexchange.org/software/free-exchange-tools/

in additon to the above, the fee tools wont monitor everything, although from your post it seems like you want to monitor the basic. You can in addition always setup a mamagement server/pc and load sysmon/perform and add the counters for Exchange/OS related counters. http://technet.microsoft.com/en-us/library/bb201720(EXCHG.80).aspx Sukh

Solarwinds Exchange Monitor looked like what I was looking for, but unfortunately it doesn't work with EX2007 :-(