Explanation for Warning severity of EXC Mailbox Size rule (4285980)

Warning severity of EXC Mailbox Size Rule definition contains the condition return #size# > registry("EXC.MailboxSize.warning"); Customer wants explanation for #size# and why the Registry variable value is set to 85.0

#size# is identified as the InformationStore size which Microsoft declared its max size as 16TB per store. Unfortunately, there is no specifically recommended store size value since it seems to be related to how many users are there(example: if there is 100 users, you could give 100GB to informationStore size). According to Exchange team blog, it is said that there's no recommended setting on the mailbox size. The main factors that limit mailbox size, practically speaking, are available disk space, backup and restore times, Service Level Agreements, and Outlook performance. http://blogs.technet.com/b/exchange/archive/2005/03/14/395229.aspx

In a community blog, the author suggest the value should be 50~100g according to his experience on exchange. http://smtp25.blogspot.com/2008/12/recommended-mailbox-size-and-exchange.html

If the default threshold value of 85m is unacceptable then customer will need to change it to an appropriate value for their environment, the unit is megabytes. Foglight is a fully customizable solution and thresholds and rules need to be evaluated and configured to meet the customers business needs.

Defect ID {EXC-175} logged to investigate further reasonable default threshold value and will be evaluated for a future Release

Please refer to the “Resolved Issues” section of the Product Release Notes when new releases are available to identify if a fix for this defect has been implemented. Product Release Notes are available in the “Product Documentation” area of our Support Website at support.quest.com