How to upgrade SQL Server Express edition to full version?
KB Article #:
86812
Summary:
How to upgrade SQL Server Express edition to full version?
Description:

You have purchased SQL Standard and need to know how to upgrade the existing SQL Express version on the server 

Resolution:  

To perform an in-place upgrade from SQL Express to SQL Server Standard edition:  

  1. Start the SQL Server 2014 installer, click on the Maintenance tab and here you see the option Edition Upgrade, launch this option. 
  2. Select the radial button before Enter the product key and click on Next. 
  3. Read the License Terms carefully and if you want to continue the upgrade, accept them by ticking the before I accept the license terms., after that click on Next. 
  4. After you click  Next, the Global and Edition Upgrade Rules will perform some checks, if this check goes without any problems the Select Instance step is shown automatically.  
  5. Select the AXIUM instance of SQL Server and click on Next.  
  6. The Feature Rules step will perform 6 checks and again if no errors occur, you'll be brought to the Ready to upgrade edition step. 
  7. Here you can see the summary of features that will be changed, if this is looking good, click Upgrade.  
  8. After the upgrade is complete, you can close the window. 
 
Details  
 
To view full details, log in with your Deltek Support Center account.