ccmcache folder and windows update in sccm 2012

[hadi 2]

I was looking for a folder that have large size in my c drive .soddenly I've found ccmchache folder with 5GB .I change the cache size on clients nicely to 500 MB.

but after a week that sccm wanted to install update on clients I faced with too many updates about 50 Updates that should be installed .I let them install .after restarting windows I saw some of the Update hasn't be installed .

on the other hand some of updates that I had defined to be required to install and I expect them install automatically But some of them become an available update and waiting for user approve to install .

whats the solution .?please .