While looking for an authoritative source for the missing Msvcr71.dll that is needed by a few old applications, I stumbled across the MSDN article Redistribution of the shared C runtime component in Visual C++. The advice given to developers is to drop the DLL into the application's directory instead of system32 since DLLs in this directory are considered before the system paths.

What can/will go wrong if I (as an administrator, not a developer) decide to take the lazy path and install Msvcr71.dll (and Msvcp71.dll while I'm at it) into the system32 directory (of 32 bit Windows XP or Windows 7 systems) instead of putting a copy in each application's directory? Is there another good solution to provide the applications with the needed DLLs that doesn't involve copying stuff to the application directories?