- Back up the registry.
- Start Registry Editor. To do this, click Start, click Run, type regedit,
and then click OK. - Locate and then click to select the following registry sub key:
HKEY_LOCAL_MACHINE\Software\Microsoft\NET Framework Setup\NDP
- After you select the subkey that is specified in step 3, point to New on the Edit menu, and then click Key.
- Type WU, and then press ENTER.
- Right-click WU, point to New, and then click DWORD Value.
- Type BlockNetFramework451, and then press ENTER.
- Right-click BlockNetFramework451, and then click Modify.
- In the Value data box, type 1, and then click OK.
- On the File menu, click Exit to exit Registry Editor.