WSUS patches will not install – Large CBS log file
There are several instances and variations but your automatic updates will indicate “files in use/locked” information or “corrupt patch” information. This is almost always accompanied by a very large CBS log file. (%windir%\logs\cbs\cbs.log) Windowsupdate.log file may indicate something similar to this: 2014-11-07 15:42:17:069 328 e9c Setup WARNING: CBS EvaluateApplicability returned error, error = 0x80070BC9 2014-11-07