If you are having problems with a file always being accessed by an unknown process, get WhoLockMe . It will tell you what process has latched into the file. You can then try to kill the process that is locking the file so you can get access to modify or remove the file. A program I haven't tried yet but is supposed to work well is Unlocker . Like WhoLockMe, Unlocker will find processes that are latched into a file. Unlike WhoLockMe, Unlocker allows you to try unlock the file from the processes from the program itself. Give it a try and let us know if it helps you change your MSVCRT.DLL file.
You didn't specify which version of Windows you are running.
I found a few Knowledge Base articles that apply to Windows 98:
Error Message: "Explorer caused an invalid page fault in module Kernel32.dll"
HyperTerminal Caused an Invalid Page Fault in Module Msvcrt.dll
Error Message After You Install a Microsoft Reader
Error Message: TASKMON Caused an Invalid Page Fault in Module...
Err Msg: An Unknown Error Has Occurred During Installation
Error Message Typing Address in Address Box or in Open Box
Indications of Virus Infection from the W32/KRIZ Viruses
Invalid Page Fault Opening Control Panel
This KB article refers to most versions of Windows:
You receive an "Invalid page fault" error message when you try to view the contents of a folder or its subfolders by using Thumbnail view in Windows Explorer
This KB article refers to if you are running Symantec's Norton Cleansweep:
Err Msg: Invalid Page Fault in Module Apitrap.dll
Give these articles a try. See if they apply to your system and if they can fix your problems. Let us know what happens.
By the way, you don't need to create a new thread each time you come back to the same problem, you can just add a new reply to your previous thread saying that the problem is still continuing. This will help us out because we won't have to find and read your previous posts to get a full idea of what's going on.