Shared files are "general purpose" files more than one program can use. They usually come in the form of DLL files, and should be automatically installed with the software that needs them (assuming the setup program for the software includes them.
DLL (Dynamic Link Library) files are basically "support" files for certain types of software. They are generally (but not always) found in your Windows System directory.
They work like this: Let's say a program needs to perform an operation. Rather than all the coding being built into the program, it uses a particular DLL file that, with a simple call, can perform the operation for it. Saves lots of programming time, especially since many of the common DLL files are already installed with Windows.
I've also had lots of people ask about deleting these files. Well, the best advice is not to, since many of your DLL files are used by more than one program. Going through and deleting the ones you *think* aren't being used anymore is a lot like getting under the hood of your car and yanking wires that don't look important. What happens if one of those shared files gets deleted or corrupted and one of your other programs will no longer run? Easy - just re-install the program in question and you'll be back in business. No big deal.
If you're really concerned about stray DLL files, make sure you run uninstall programs. Most programs include an uninstall program that will (should) take out all the extra DLL's.
There are programs available that will check your shared files to see if they are needed, but again these aren't always fool-proof.
Sometimes when uninstalling a program a message comes up telling you that there are shared files that may not be needed on your system, "Would you like to remove?"
All of us want to conserve space on our hard drive, so of course, the natural impulse is to click "yes". Guess what? You may have actually removed files that another program does need. I get so many calls from readers who experience "***.dll file not found" errors after uninstalling software.
So, if you are asked if you want to remove a shared file, it may be best to click "no". Going through and deleting the ones you *think* aren't being used anymore is a lot like getting under the hood of your car and yanking wires that don't look important.
What happens if one of those shared files gets deleted or corrupted and one of your other programs will no longer run? Easy^DDLjust re-install the program in question and you'll be back in business. No big deal. If this still doesn't put back the missing .dll file, check out this site...
Simply type your missing file name into the search box to find if it is available, then download it. You can also go to the "dll-files downloads" page and scroll down the alphabetical list to find the file you need. After downloading the most likely place to put the .dll file is in the Win32 folder, if that doesn't work, try the program's folder.