| Service Pack 3 (SP3) and later for Exchange | | | | supported. |
| Server include several security and performance | | | | You might also receive an event with 9519 ID |
| enhancing improvements that provide the user | | | | that suggests it failed to attach Jet DB. |
| more customized experience. You are | | | | Cause |
| recommended to always perform a complete | | | | Exchange Server SP3 and later cannot mount |
| database backup before installing the update on | | | | compressed information store databases. This is |
| your Exchange Server computer. This is because | | | | because compressing database files invalidates |
| installing the update and upgrading Exchange | | | | sector independence, which is required by ESE to |
| Server might render the database unmountable. | | | | perform log-based recovery. So, if pre-SP3 |
| In such cases, you require to use your current | | | | Exchange Server contains NTFS compressed |
| database backup to restore it or perform | | | | database, it will not mount. Also, such compressed |
| effective Exchange Server Recovery using | | | | databases can get corrupted |
| third-party tools. | | | | Solution |
| To exemplify, consider that you use Exchange | | | | To isolate the given issue, use the following |
| Server 2000 SP2 and attempt to upgrade it to | | | | sequence of steps: |
| Exchange Server 2003. When you try to mount | | | | 1. |
| the database, you might come across the below | | | | Dismount all the databases |
| entry in application log of Event Viewer: | | | | 2. |
| Event Type: Error | | | | You can then decompress the folder of logs and |
| Event Source: ESE | | | | databases |
| Event Category: General | | | | 3. |
| Event ID: 505 | | | | Use eseutil /d to perform offline defragmentation |
| Description: Information Store (2028) An attempt | | | | of databases |
| to open the compressed file | | | | However, if you find your database corrupt due |
| "drive:\Exchsrvr\MDBDATA\priv1.edb" for read / | | | | to NTFS compression, you should restore from |
| write access failed because it could not be | | | | the available backup. If this doesn't give the |
| converted to a normal file. The open file operation | | | | desired outturn, you need to use an Exchange |
| will fail with error -4005 (0xfffff05b). To prevent | | | | Server Software to repair and restore the |
| this error in the future you can manually | | | | database. Exchange Server Recovery tools |
| decompress the file and change the compression | | | | employ high-end database repair algorithms that |
| state of the containing folder to uncompressed. | | | | too reliably and safely. |
| Writing to this file when it is compressed is not | | | | |