This is a known issue and is covered in IE4.TXT, which is the read
me file that comes with Internet Explorer 4.
If you must reinstall Windows NT 4.0 Service Pack 3 (SP3) after you
install Internet Explorer 4.0, you must specify when prompted that you do not
want it to overwrite any files that are newer. After SP3 is reinstalled,
carry out the following steps to update the registry:
1. Click the Start button, and then click Run.
2. Type the following: regsvr32 rsabase.dll
3. Click OK.