删除dll时出现System.UnauthorizedAccessException（C＃）

Question

Please read carefully: I know that dlls can be in use. I also know about NTFS permissions, and read-only flag.

1. I create a text file with content hello.
2. I rename it to .dll
3. I try to use File.Delete(...) method to delete it: I got System.UnauthorizedAccessException
4. I try to open it with File.OpenWrite(...) I got the same exception.
5. I've turned out all virus checking software.
6. I am admin in my Windows 7 machine.
7. I am the owner of the .dll extension file
8. I can it delete without any warning from the UI.

Using VS 2012 C# program (.NET 4.5)

Any ideas? Thanks

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SOLVED: (partly): This was my firewall :-(. Somehow it cached and sandboxed my project output executable, and restricted to delete .dlls (not .txts). Although I turned off it, and I rebuild the .exe many times somehow the named exe sandboxed state remained active. I stress it was a many times rebuild and binary changed .exe. Congratulations to Commodo just 2 erratic behaviour in on issue. 1) Why the sandboxing is still active if antivirus has turned off? 2) Why not reevaluate the named .exe file and asking me about sandboxing if the binary has changed? How this is turned out? I renamed the project output to x.exe :-(

This was more the 45 minutes from my life and worktime...

Answer 1

For delete try

File.SetAttributes(file, FileAttributes.Normal);
File.Delete(file);