Drives used for SQL databases are running out of free space.

Reason:   One or more of the following might be causing this:

1. Size on the drives are not sufficient .
2.The problems at the URL Expired-sessions-are-not-being-deleted
3. Perhaps the SQL error log is spamming and has filled up the entire C drive.

Resolution:
1. The resolution to the Expired-sessions-are-not-being-deleted will take care of it (partially).

2. Manage the Size of the SharePoint_Config Database :
The SharePoint Config database can grow to a large size and you need to make sure to maintain this (and all other SharePoint Databases).
Follow these steps to shrink the SharePoint databases:
[Make sure that you have enough disk space available before this procedure]

1.      Start SQL Server Management Studio and look at the Disk Usage Report

4.      Take a full backup of the SharePoint_Config database

5.      Take a transaction log backup of the SharePoint_Config database

6.      Now, configure the Config Database > Properties > Options > Recovery Mode = Simple

7.      Run DBCC ShrinkDatabase(SharePoint_Config, 10)

8.      Configure the database back to Full recovery mode Properties > Options > Recovery Mode = Full

3. Follow the Checklist specified below:
 Checklist to free space
1. Cycle the SQL errorlog to remove large error log files from the C drive - see script below
2. Clear out old mdf and ldf files from the \Data directory
3. Clear out old stack dumps and crash dumps from \LOG directory
4. Remove any redundant backup files
5. Delete old roaming user profiles from C:\documents and settings
6. Check any \temp directories and .tmp files for files to delete
7. Empty the Recycle Bin.
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