Client appear on SEPM but not updating though definition available.

I have a SEPM server still on 11, the embedded database was corrupt. I thus uninstalled it and reinstalled it on the same server. I used the keystore.jks and Domain ID of existing server; I can see that all clients are appearing on the new installed server. Latest virus definition has already been downloaded on the server, but problem is that none of the clients are updating. Can you please help me out. There is 30 client and I don't want to end up having to sylink each of them.

Thanks,

Arvind