Deleting file, but is access denied

Building upon the answer - For me I had to set the folder and the files inside it to normal attributes.

    DirectoryInfo directory = new DirectoryInfo("/path/to/file");
    directory.Attributes = FileAttributes.Normal;

    foreach (FileInfo file in directory.GetFiles()) {
        file.Attributes = FileAttributes.Normal;
    }

I also had the problem, hence me stumbling on this post. I added the following line of code before and after a Copy / Delete.

Delete

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

Copy

File.Copy(file, dest, true);
File.SetAttributes(dest, FileAttributes.Normal);