Microsoft announced the release of their now updated .NET Framework Repair Tool so that it now includes the latest releases of the Framework which includes both versions 4.5 and 4.5.1. This announcement was made in their .NET Framework blog. The tool was specifically designed for fixing problems with the installation of the Framework itself or updates that cannot be fixed from within the setup of the application. The latest .NET Framework Repair Tool release is available via the Microsoft Download Center and it can be used through the GUI or via command line arguments and both versions of the .NET Framework can be targeted for fixing, or all versions. Additional new features of the tool include a new "Log Collection Only" mode which provides logs only for the .NET Framework setup, and an Offline Repair mode, plus a new "Quiet/Passive Mode" which is Microsoft's term for the command-line switches and is intended for organizations that want to automate the fixes. Those fixes may include changes to the Windows Installer service, corrupted registrations or discretionary access control lists (DACLs) on certain folders. The tool automatically scans a system for common or known setup failure issues. Read the full details here.
With previous versions of the .NET Framework tool covering only up to version 3.5, the tool is now current.