Downgrade from 128-bit to 40/56-bit security

I used to have a computer located in the US. That computer is running Windows NT4 Workstation with SP5 and 128-bit encryption. It is running IE5.

I have since moved that computer out of the US. I need to install SP6 on that computer - naturally, I cannot download the 128-bit version of SP6 as I am not located in the US anymore, but the 56-bit low encryption version of SP6 refuses to install on my high encryption copy of SP5.

So I need to know, is there any way to downgrade my cipher strength to either 40 or 56-bit so that I can use the SP6 installer that I have. Or is there any other workaround?

I need a good and complete solution, since this is our web server, and I do not want to do anything that would compromise the stability of the OS, as far as possible.

Please ask for any more information required.
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TedSennConnect With a Mentor Commented:
The encrip[tion bit rate is defined in a file (.dll I think). The exact name eludes me but a search of M$ site may turn up an answer.
aliebrahAuthor Commented:
Edited text of question.
Did you leave the uninstall for SP5?

Unistall SP5 >Start >Settings >Control Panel >Add/Remove Programs >Service Pack 5 >Look for 128 remove it first!!, then load preq SPs then SP6

If you can not do the above back up the data on your drive(s) then blow it all away and rebuild.. Sorry I hope someone else has a better answer...
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aliebrahAuthor Commented:
Unfortunately the person who installed SP5 on the system didn't leave the uninstall files. So this isn't an option for me. Does someone else have a better solution?
A reinstall of 40/56 bit SP5 may also work.
aliebrahAuthor Commented:
TenSenn I'll check out your suggestion and let you know if it works.
SP6 is available and you can install the non 128 bit encryption of that.
aliebrahAuthor Commented:
celtics no I can't because thw non 128-bit SP6 will not install on a 128-bit system.
aliebrahAuthor Commented:
>A reinstall of 40/56 bit SP5 may also work.

I tried this. When I installed 40-bit SP5 it told me that if I proceeded it would downgrade cipher strength to 40-bit. I did the SP5 install. Upon reboot, I was back to 128-bit again (which is wierd since I was told I'd be back to 40-bit), and SP6 setup again refused to run.

By the way, upon reboot, Windows spawned a console app which I think was called cvsroot.exe (or something similar). I'm not sure if this had to do with the encryption or was just part of SP5 setup completion.

Any other suggestions?
aliebrahAuthor Commented:
I wasn't able to find anything helpful on the Microsoft site (anyone surprised?).
aliebrahAuthor Commented:
Actually I did find something useful on the Microsoft website after all:

According to this page, I have the following files on my computer (after reinstalling 40-bit SP5):

Ndiswan.sys - 40 bit version
Ntlmssps.dll - 40 bit version
Schannel.dll - 128 bit version
Security.dll - 40 bit version
Rsaenh.dll - 128 bit version

This is probably helpful information to find the solution.
aliebrahAuthor Commented:
I'm not giving an A grade because TedSenn did not really provide me with a complete solution, but pointed me to how to solve the problem rather. It was his combination of thoughts that led me to the solution. This is how I did it:

Having been to Microsoft's website:

I noted that 2 files I had were 128 bit and were causing the problem (read my last post).

I renamed Schannel.dll in C:\WinNT\System32 to Schannel.128 and I renamed rsaenh.dll (in the same folder) to rsaenh.128. I then unextracted the 40-bit SP5 setup and took the Schannel.dll from there and copied it to C:\WinNT\System32.

After I did this, I checked and sure enough the encryption was back to 40-bit. I was then able to install 56-bit SP6 without any problems!
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