I just checked few machine and found that Plugin Flag value in register is 0 but still those system's VSE are not reflecting in ePO.
I also tried uninstalling the product and installing it again, but it worked only on a single system.
Most of the system in this problem does not have duplicated entries. so this Moving GUID to Duplicate List and Delete System and Plugin Flag are not working so can anyone please suggest me any other solution..
Let's one more try from ePO for VSE install on some machines.
Create VSE install Client task and add below in command line.
IMPORTANT: The switch REINSTALLMODE must be in CAPITALS.
Thanks, some more system have started reflecting in my ePO ..but the ePO server itself is not reflecting the VSE ..
Now check plugin flag value on those machines and if its set to 8.