Warning: You REALLY don't want to be deleting any DLL files.
They are system files and deleting any can (and will) cause programs to quit working, Windows to stop working, etc.
However, if you absolutely insist on deleting it, here's how (it's not as easy as you may think)
(Disclaimer: This is not my work and don't claim it to be so. All credit goes to How-ToGeek)
Open an administrator command prompt by typing cmd into the start menu search box, and hit the Ctrl+Shift+Enter key combination.
To take ownership of the file, you’ll need to use the takeown command. Here’s an example:
takeown /f C:\Windows\System32\en-US\winload.exe.mui
That will give you ownership of the file, but you still have no rights to delete it. Now you can run the cacls command to give yourself full control rights to the file:
cacls C:\Windows\System32\en-US\winload.exe.mui /G geek:F
Note that my username is geek, so you will substitute your username there.
At this point, you should be able to delete the file. If you still can’t do so, you may need to reboot into Safe Mode and try it again. For the filename in the example, I was able to overwrite it without safe mode, but your mileage may vary.
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Yours,
Hugh
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