Unable to delete projects from Primavera P6 Optional Client 8.1

Dear Oracle Team/ Users,

I am facing the subjected error while deleting projects from P6. Kindly advise me the solution.

Primavera P6 Version 8.1.0 Build No. 831

Database - MS SQL Server 2008 R2

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*                EXCEPTION  REPORT                  *

*****************************************************

Date:          01-Mar-16

Executable:    PM.exe

Application:   Primavera P6 Optional Client R8.1 Project Management

Event Code:    PRMDB-1704-8

Message:      

  PRM DBAccess Error: Could not allocate space for object

  '<temporary system object: 422233321308160>' in

  database 'tempdb' because the 'PRIMARY' filegroup is full.

  Create disk space by deleting unneeded files, dropping

  objects in the filegroup, adding additional files to the

  filegroup, or setting autogrowth on for existing files in the