Replacing msvcrt.dll

How can I replace the system dll msvcrt.dll from within NT? Using Explorer or the DOS prompt!
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Tim HolmanCommented:
Before you replace it, make sure you have an up to date recovery disk !
You could install another copy of NT into a seperate directory, boot up with that one, and swap the files over in the original directory ?
Otherwise, there are some registry keys that allow for 'offline' file renames :

look at :
Or you can rename msvcrt.dll to msvcrt.old, copy your new version to msvcrt.dll, and then reboot.
maweAuthor Commented:
Actually, renaming the file from the DOS prompt and then replacing it did the trick! Thanks anyway!!
Tim's suggestion will work.  Also there is a utility from Microsoft called INUSE. You can find it by doing a search for INUSE on Microsoft's search page.
The simple answer is that manually you can't easily replace it, as it's in use all the time.  First of all, you need to know which version of the the file you need to change it to.  MSCVRT.DLL is a C++ Runtime library, this is included in the MS Data Access Components update, which you can get off the Internet.
If you download MDAC, there are several different version, even for the same release, i.e. you may download MDAC 2.1, but you may have MDAC 2.1.z.y, or MDAC 2.1.x.w, and there are several more versions of MDAC.  These different version of MDAC contain different version of MSVCRT.DLL.
To find which verison of MSVCRT.DLL aversion of MDAC contains, you need to expand it.  One of the setup switches for the MDAC install executable lets you expand the EXE without installing it, so you can see what files are installed.
You can then look at the properties of the new MSVCRT.DLL file and if it's the one you want, you can install that version of MDAC.
Once you've installed the new version of MDAC, you'll need to reboot your server for the change to take place.
The only other way is to create your own EXE that installs the version of MSVCRT.DLL.  You can do this simply with the MS Installer that is part of MS Systems Management Server.

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