In this we will go through the problem of database dismounting due default (or underestimated) size limit for exchange database. I will show you how easily you can set exchange database size limit using regedit in various editions of exchange server.
Why to change or set exchange database size limit at all?
The question comes to mind that why do you need to change the default size limit. The answer is simple see the below screen error which tells clearly that the current physical size of this database (the .edb file) is < GB. If the physical size of this database minus its logical free space exceeds the limit of 50 GB, the database will be dismounted on regular basis.
Step by Step Guide to set Exchange Database Size Limit
You can set exchange database size limit according to your organization need and it also depends on the edition and version of Exchange Server you are running. If you are running older version of Exchange Server like 2003 then you can set limit only up to 75 GB (for standard edition) or 8,000 GB (for Enterprise Edition). For later version of Exchange Server the database size limit is increased to 16 TB which is technically unlimited. But in order to change the default set exchange database size limit you need to made some changes in the registry setting of your system. Here the step by step procedure to set exchange database size limits using registry settings:
Note:
- Incorrectly editing the registry can cause system failure. So be careful
- All of registry values mentioned in this post are in decimal, not hexadecimal.
Step 1: Open Regedit and browse to the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\<Server Name>\Private-<database GUID>
If the “Database Size Limit in GB” DWORD does not exist for the subkey then create a new DWORD “Database Size Limit in GB”, and then set its decimal value to the desired size in gigabytes.
Note: You need to restart the information store service to see the changes in the database size limit.
Step 3: Restart Exchange Information Store service.
Step 4: Check event viewer for confirming the change is size limit.
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