subject: Help! A New Program Overwrote My Computer's DLL Files! [print this page] Help! A New Program Overwrote My Computer's DLL Files!
What are DLL files?
Computer programs often refer to a common library of files in order to carry out basic functions such as printing. These files, called Dynamic Link Library (DLL) files, are used by programmers to program common tasks without having to write original code from scratch. Windows computers come with a set of DLL files which are then referenced as needed by computer software and devices.
Missing DLL files
Unfortunately, these files don't always cooperate. Sometimes they simply disappear. Files of all types, including Dynamic Link Library files, can be accidentally deleted, gobbled up by malware, or corrupted due to an unexpected shutdown. When this happens, functions requiring the missing DLL file can no longer be executed. For example, your all-in-one printer may suddenly refuse to scan documents, your mouse might stop responding, or one of your programs may display odd computer error messages saying that a required system file is missing, corrupt, or can't be found.
Overwritten DLL files
In addition to mysterious missing files, adding new software or hardware to a computer can overwrite DLL files. This can happen when the developer opts to use an older or newer version of a given file. When the software installs, it replaces the computer's current DLL file with the program's required version. This is terrific for the new program or hardware because the computer now has the correct version of the file for the smooth operation of that new program or device. However, your computer's other programs or devices may not recognize or work with the replaced DLL. Again, your computer may exhibit program errors and its devices may stop working.
Removed DLL files
This works both ways. When you uninstall a program or device, you may be prompted to remove "unnecessary shared system files." When this happens, the uninstaller may be removing DLL files that it doesn't realize that other programs and devices need. As with missing DLLs, these removed files could lead to computer errors and devices that do not work as expected.
Overcoming Missing, Overwritten, or Removed DLL Files
The key to overcoming these problems is considering what may have affected the files in the first place. Has your computer recently crashed? If so, the files could be corrupt. Your best bet is to perform a System Restore, choosing a restore point from just before the crash. If you recently installed a new program, pay attention to which programs and hardware it is affecting. If you want to keep the new program, you may need to reinstall or repair (if offered) the older affected programs. If you recently uninstalled a program and allowed it to remove the "unnecessary shared system files," reinstall the program and then uninstall it once again, this time leaving the shared DLL files in place.
DLL files are necessary and vulnerable to occasional problems such as the ones discussed above. While not exhaustive, these three troubleshooting tips may be all you need to overcome your missing, overwritten, or replaced DLL files.
