Restore backup failure question

System.IO.IOException: The process cannot access the file because it is being used by another process.
at System.IO.FileSystem.MoveDirectory(String sourceFullPath, String destFullPath)
at System.IO.Directory.Move(String sourceDirName, String destDirName)
at MailClient.DbBackup.FormBackup.Restore(String backupFile, CancellationToken cancellationToken)
at MailClient.DbBackup.FormBackup.Restore(CancellationToken cancellationToken)
at MailClient.DbBackup.FormBackup.<>c__DisplayClass27_0.<MainForm_Load>b__0(Object a, DoWorkEventArgs b)
at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)
at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)

It is possible the file is locked or blocked by your OS or another app.

You can restart Windows, and then try the restore again.