E00.log is Missing and Database Doesn't Mount with Event 9518 and 455

Transaction log files is the disaster recovery method used by Exchange Server to bring its databases to a consistent state post crash. The current transaction log data for a database is stored in E##.log file, which is further renamed to E#######.log when reaches to 5MB in size. The '##' is basically the storage group identifier. Thus, for first storage group, the file is E00.log. The file may go missing or get corrupt It generally occurs because of antivirus scanning and can render the databases unmountable as a consequence. At this point, you should remove all the transaction log files from the root folder and try to mount the database. If the problem continues, Exchange database corruption might be the reason. So, you need to use Exchange Recovery solutions to repair and restore the files.

For instance, when you try to mount a mailbox or public store of Exchange Server 2000 or 2003, the operation might fail. When you view the application event log, you may come across events 9518 and 455.

Cause

E00.log file is missing or corrupt. This could occur if an anti-virus program is scanning or if anti-virus quarantine option is enabled for Exchange files.

Microsoft suggests excluding Exchange databases, temporary files, logs, the IIS system files and the IFS drive from antivirus scanning on computer running Exchange Server. Also, it is recommended to avoid the scanning of folders that contain these files. By default, the folder containing temporary data is \Exchsrvr\MDBData. If your anti-virus software is scanning this folder, it might take the 'E00.log' as a virus or a file containing the virus. As a result, it will quarantine the 'E00.log' file and cause Exchange Server to crash.

Solution

1. Stop all the Exchange services and exclude its files from antivirus scanning

2. Move all the log files from \Exchsrvr\MDBData to a temporary folder, except E00.chk, Res1.log and Res2.log

3. Start all the Exchange services and try to mount the databases

4. If you still cannot mount the databases, the problem lies is databases. They might be corrupt. Run eseutil /p to perform soft recovery, restore from backup or use a third-party Exchange Recovery product. Exchange Server Recovery utilities incorporate high-end scanning algorithms that can safely repair a damaged Exchange database and extract data from.

Stellar Phoenix Mailbox Exchange Recovery is a powerful and safe utility to provide systematic repair for corrupted Exchange databases. It supports Exchange Server 5.5, 2000 and 2003. The tool can perform comprehensive Exchange Recovery for all database objects and extracts user mailboxes in individual PST files.