edit the system.ini
change the line shell=explorer.exe to shell=winfile.exe
bootup.
run setup.exe for internet explorer.
i ran the file from the program files\internet explorer folder.
uninstalled ie5.5
change the line back in system.ini and reboot.

Check out Microsoft KB documents Q175930 and Q129605 for a solution. Read those and note that if you are extracting from CAB files on your hard drive (which you would do if you are running IE 5.0 or 5.5) through DOS, your directory will probably be c:\window~1. The file you need is shdocvw.dll and it is found in IE_1.CAB of IE_S1.CAB if you are using IE 5.0 (extract IE_S1.CAB to a directory first, then use extract to extract the shdocvw.dll file)and in IE_2.CAB of IE_S2.CAB if you are using IE 5.5. If you are running Win 95 or Win 98SE or Win ME, they have instructions for those, also.

OR

I had this problem going from ie4.0 to ie5.5 in windows 98. Here is how I recovered.
-Booted into command prompt holding cntl key at boot
-went into c:\windows\command and ran edit
-editted the system.ini in c:\windows
-change the shell from explorer.exe to winfile.exe
-reboot and the pc will look like windows 3.1
-reinstall ie 5.5 from cd by clicking on the ie5setup.exe on the cd (you may have to play with typical vs full install)
-reboot as suggested but boot in SAFE MODE by holding cntl
-once in winfile edit the system.ini again and change shell back to explorer.exe
-reboot making sure again to go into safe mode
-windows will grind for a while changing settings
-once in normal desktop shutdown
-reboot in normal mode
-windows will update drivers quickly then all clear

NOTE: At some point I also updated the demon dll's (msvcrt, msvcrt20 and msvcrt40) from another machine.

This problem can be caused by an excessively long file extension entry in the registry. To fix:
- Open Regedit (Start, Run, type "regedit" without the quotes)
- Click on plus sign "+" beside HKEY_Classes_Root
- Scroll thru all the extensions (starting with ".")
- If you find a long one, right click on it and click "delete"
- Continue checking thru all the extensions listed
when i did this, i only removed lines that had HOTBAR written in the line....Worked great!!! and i am no computer wiz, this was easy!

I went into registry and did the hotbar delete of one file and it fixed my problem with SHDOC401.DLL at015f:" Thanks for the help.

remove long name extensions from HKEY_CLASSES_ROOT

I have found it is linked to Hotbar. Hotbar is a tool for IE I downloaded. I removed it a while back and it left a registry entry. It was along one under
HKEY_Classes_Root
.dll_GetPromo&El=bc%3bhotbar%5felement%3b&SG=&RAND=27894_
I delted that key and I am creating New Folders again.