Hi,
Resetting the catroot2 folder is basically known to fix many Windows Update problems.
Catroot and catroot2 are actually the Windows operating system folders required for Windows Update.
When you run Windows Update, the folder catroot2 stores the signatures of the Windows Update package and also helps to install it. The Cryptographic Service actually uses the % windir% System32catroot2edb.log file for the update process. Updates are stored in the SoftwareDistribution folder, which is then used by Automatic Updates to perform the update.
Do not delete or rename the Catroot folder. The Catroot2 folder is recreated automatically by Windows. However, the Catroot folder is not recreated if it is renamed.