This generally means you have damaged system files. If you can open an elevated command line (unfortunately, you didn't tell us which operating system you're using but generally, typing "command" in the search window, then RIGHT click on the "Command Prompt" or "Command.exe" listing at the top, choose "Run as Administrator". ) , one it's open type: "sfc /scannow" (without the quotes) and press "Enter". The System File Checker should run and identify any corrupted system file and replace them. That's if you're lucky. Sometimes it can't replace them. If that's the case, then you'll need to obtain an operating system disk from which you can boot and run a repair Windows install. It may be your best bet.
Also....The link below has a good discussion about the issue. It provides a number of fixes including one that involves downloading and installing Microsoft C++ Redistributable. If you need to perform a download, simply borrow a friend or family members computer to download the file, transfer it to a USB flashdrive or CD, then move it to your problem machine.
https://blogs.msdn.microsoft.com/cesardelatorre/2011/03/27/the-application-has-failed-to-start-because-its-side-by-side-configuration-is-incorrect-error-related-to-mmc-exe-programs-and-weird-cause-simple-solution/
Hope this helps.
Grif
So recently my computer has stopped letting me open any applications and download anything (notice that i said i can't download anything, please do not reply telling me to download something to fix it. I CAN'T). It comes up with an error message that is different every time but still gets across the same message, for example when i try to open Steam:
C:\Users\(My name)\Appdata\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Steam.Ink
"The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log or use the command-line sxstrace.exe tool for more detail."
I cannot open or download anything on my computer and i REALLY need a fix for this, any ideas?

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