Error:

The Setup has encountered an unexpected error while updating installed files. The error is: Access is denied

Snapshot:

Causes:

Following local policies must have Administrator rights

Local Policy Object Display Name                         User Right
Backup files and directories                                           SeBackupPrivilege
Debug Programs                                                              SeDebugPrivilege
Manage auditing and security log                                  SeSecurityPrivilege

Workaround 1:

Make sure that you are running the SQL Server setup as “Run as Administrator”.

Workaround 2:

To add the rights to the local administrator account, follow these steps:

1. Log on to the computer as a user who has administrative credentials.
2. Click Start, click Run, type gpedit.msc, and then click OK.
3. Double-click Computer Configuration,  clickWindows Settings.
4. In the Securtiy Settings, click Local Policies, double-click User Rights Assignment, and then double-click Backup Files and Directories.
5. In the Backup Files and Directories Properties dialog box, click Add User or Group.
6. In the Select User or Groups dialog box, type the user account that is being used for setup, and then click OK two times.
7. Repeat the procedure for the other two policies that are mentioned in the “Cause” section.

Workaround 3:

Click Start | Run | type regedit | Click OK.

Open “HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\WMI”

Right click on “Security” and give full control permission for Administrator.