Hi Email Tech, Firstly, please try to increase the online maintenance window for the database: How to Set the Maintenance Schedule for a Database http://technet.microsoft.com/en-us/library/bb629590(v=exchg.80).aspx If the event still appears, please check whether Outlook users have the CRM Outlook Plugin installed. Last but not least, if you place the database and logs on C drive(C:\Exchange\Database.edb), suggest you move the database and logs to another larger volume. Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com. Frank Wang TechNet Community Support

I am running Exchange 2007 and have a recently created database that is throwing an event id 628 in the logs. Can anyone help with this. Maintenance is running 4 hours each night. The database size is 72GB. Below is the log entry. I created the database only a week ago. Event Type: Warning Event Source: ESE Event Category: Performance Event ID: 628 Date: 8/7/2012 Time: 12:30:17 PM User: N/A Computer: Exchange Description: MSExchangeIS (6756) Exchange: Database 'C:\Exchange\Database.edb': While attempting to move to the next or previous node in a B-Tree, the database engine skipped over 1612 non-visible nodes in 29 pages. It is likely that these non-visible nodes are nodes which have been marked for deletion but which are yet to be purged. The database may benefit from widening the online maintenance window during off-peak hours in order to purge such nodes and reclaim their space. If this message persists, offline defragmentation may be run to remove all nodes which have been marked for deletion but are yet to be purged from the database. Name: MDB Event History Table Owning Table: MDB Event History Table ObjectId: 54 PgnoRoot: 114 Type: 2 Unversioned Deletes: 0 Uncommitted Deletes: 0 Committed Deletes: 0 Non-Visible Inserts: 1612

Can you check your event logs and see how long its taking to complete a full pass on for online maintenance?James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

Hi Email Tech, Any updates?Frank Wang TechNet Community Support

Hi Email Tech, Firstly, please try to increase the online maintenance window for the database: How to Set the Maintenance Schedule for a Database http://technet.microsoft.com/en-us/library/bb629590(v=exchg.80).aspx If the event still appears, please check whether Outlook users have the CRM Outlook Plugin installed. Last but not least, if you place the database and logs on C drive(C:\Exchange\Database.edb), suggest you move the database and logs to another larger volume. Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com. Frank Wang TechNet Community Support