I was recently working on a SharePoint Migration Project where we migrated from a SharePoint 2010 farm to a shiny new SharePoint 2013 SP1 farm. Some of the sites were to stay in “2010 Site Collection Mode” until the site owner was ready to upgrade and others were upgraded to 2013 right away. Below is a screenshot or Central Admin showing the database upgrade status for 3 content databases:

  1. The top database was completely upgraded to 2013. Looks beautimus!
  2. The middle database has some sites upgraded and others in 2010 mode…Looks OK..
  3. The bottom database SHOULD have some site collection in 2010 mode and others in 2013 mode just like the middle database. Something looks off here right? Running the Upgrade-SPContentDatabase cmdlet did nothing and PSConfig did nothing.

CADBTooOldError

Looking at the eventvwr Application Log shows some interesting new errors:

eventvwrdbtooolderror

Nothing has changed in the farm from a SharePoint Server perspective…I was able to run the Get-SPContentDatabase command on each content database in this state and get back the appropriate webapp object for each. When clicking the content database anywhere in Central Admin I would get the error “Object Reference not set to an Instance of an Object” and this was causing other errors in the environment:

  1. Alerts were not working
  2. Issues with editing files/check-in and check-out
  3. Not able to select any site collection in Central Admin

Users could still get to the site collections…The experience just wasn’t optimal. I took a look through ULS, Eventvwr, and SQL Logs and couldn’t find anything besides a larger stack trace for the Object Reference Error and not much else.

Something happened between this content database and the SharePoint server causing the database to be in this funky state. PowerShell to the rescue!
The Fix: Running the Dismount-SPContentDatabse and Mount-SPContentDatabase fixed the issue.

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