I'm currently running a Win 2K3 SBS Exchange server with 3GB memory. Over the last few months I have received errors in the event viewer regard virtual memory fragmentation. The VM increases to about 6GB. I restart the Exchange services, this releases the memory used. About 700mb of physical memory is used by store.exe and it stays at that figure. During the day the virtual memory is stable but checking the following morning it has increased by up to 1.2GB at a time. The Exchange database is stable and i have no other issues. I have a hunch that the online defragmentation is causing this. I have a â€˜First storage groupmailbox storeâ€™ that states 5093MB free would an offline defrag be recommended or could this be something else?