Logon to the SEPM console
Admin --> Install Pacakge --> Client Install Package --> Add a Client Install Package
Browse to the SEP 12.1 RU1 setup files, Go to the Additional Packages folder, you will find SAVLegacy32.info, select that file
Give Specific name & Description.
Monitor Import Package Process, it may take few minutes.
We can see now SEP RU7 package is successfully added. It's a SEP RU7 32 bit setup file.
SEP 11.x package is useful if you still have Windows 2000 operating Systems. Because SEP 11.x supports Windows 2000 platform
SEP 12.1 doesn't support windows 2000.