My predecessor setup exchange with circular logging, he apparently wasn't backing up the message store. I have since revamped the entire backup system, and am doing incremental backups, which fail because circular logging is enabled. Is there anything to watch out for when I disable circular logging? I don't want to get caught and have something break on me by doing it.thanks for any info

I am not a big fan of circular logging and really the only time you want to implement it is when you have limited space on your hard drive. Saying that check your hard drive and make sure you have enough space to accomodate the log storage. Check these articles for reference: http://searchexchange.techtarget.com/tip/0,289483,sid43_gci1171496,00.html http://support.microsoft.com/default.aspx/kb/147524 Thank you Jay

The transaction log is on the system partition on the server which has 8.3gb free. I have approximately 60 mailboxes so i'm not sure if that is enough room or not, keeping in mind that I am doing incremental backups and a weekly full backup which will remove the committed transaction logs. My first thought is to turn off the circular logging since that is not the best practice in any event.

You will need to turn off circular logging to get those increments. Depending on how much mail flow occurs with your 60 boxes 8.3GB should be enough. you can also remove log files that are x days old.

I might be mis-interpreting the sentence "you can also remove log files that are x days old.". However, just to be clear: you must never manually remove transaction logs. Always allow a full backup to manage and commit transaction logs. Manually removing transaction logs could render your Exchange installation unusable. Circular logging should not be enabled as it breaks the ability to roll changes forward from the last backup (meaning that you only get restoration to the last backup. Data between that backup and when the system went down is lost. With circular logging disabled you can restore the last backup and then use the transaction logs to replay the operations to the point where the system went down. Little, if any, loss of data). As Jay states, 8.3 GB should probably be enough space to disable circular logging for a 60 mailbox installation. Monitor your disk usage closely and if you find yourself running out of space, run a full backup which will clear out the transaction logs.

I agree with David and thanks for clearing that up. What i was referring to is the option in the general tab of the server where you can remove log files after so many days, but again if you remove the log files and didn't do a backup; restoring to a point in time will fail since the logs have been deleted.