My code goes as follows:

private void btnChangeImg_Click(object sender, EventArgs e)
            using (var openFileDialogForImgUser = new OpenFileDialog())
                string location = null;
                string fileName = null;
                string sourceFile = null;
                string destFile = null;
                string targetPath = @"..\..\Images";
                openFileDialogForImgUser.Filter = "Image Files (*.jpg, *.png, *.gif, *.bmp)|*.jpg; *.png; *.gif; *.bmp|All Files (*.*)|*.*"; // filtering only picture file types
                openFileDialogForImgUser.InitialDirectory = @"D:\My Pictures";
                var openFileResult = openFileDialogForImgUser.ShowDialog(); // show the file open dialog box
                if (openFileResult == DialogResult.OK)
                    using (var formSaveImg = new FormSave())
                        var saveResult = formSaveImg.ShowDialog();
                        if (saveResult == DialogResult.Yes)
                            imgUser.Image = new Bitmap(openFileDialogForImgUser.FileName); //showing the image opened in the picturebox
                            fileName = openFileDialogForImgUser.FileName;
                            location = Path.GetDirectoryName(fileName);
                            sourceFile = System.IO.Path.Combine(location, fileName);
                            destFile = System.IO.Path.Combine(targetPath, fileName);
                            if (!System.IO.Directory.Exists(targetPath))
                            System.IO.File.Copy(sourceFile, destFile, true); //error occurs here

I can't copy the file because System.IO.IOException occurs. The message goes like: "The process cannot access the file <file> because it is being used by another process". I know I have to terminate the process using the file, but how do I know which process that is? BTW, when I say file, I am refering to the image that the user selected when the OpenFileDialog is shown.

Try to do the copying outside the using clause.

First of all quick tip for you

openFileDialog.ShowDialog() == DialogResults.OK you can stick that in an if statement (I love to do it that way).

Secondly, I see it's an image ... aka, "Royal pain in the butt when it comes to memory management".

I'd suggest trying ddanbe's idea first. However, if that doesn't work (which I don't see why not, but then again Images cause me nothing but headaches), you could always try doing something like

Image image = Image.FromFile("FileName")

Which will load the image in from a file, and then follow that up with an


And then just dispose of the Image (or you could use that in a 'using' statement). I should point out the Save does offer some other features like including the ImageFormat, if yo ucare to explore that