If you see error 66 when you try to sign into MSN Explorer, this may be due to a recent security change.
You may be able to resolve this error by following these steps:
1) Launch Internet Explorer.
2) Click the gear icon in the upper right-hand corner. (It should be located next to the Favorites star.)
3) Select Internet Options.
4) Select the Advanced tab.
5) Scroll down to the Security section.
6) Check the Use TLS 1.2 box.
7) Click Apply, and then OK.
8) Close Internet Explorer, and then try signing into MSN Explorer.
Note: If you are running Windows XP, you may not see this option. MSN Explorer is not supported on Windows XP.