Edit | Open/Close Log File
Click Open/Close Log File on the Edit menu to write to a new log file, append to an existing log file, or close an open log file.
When you click Open/Close Log File, the Open/Close Log File dialog box appears. This dialog box displays the current log file, if one is already open.
If the Log file name box is blank, you can enter a log file name. If this file already exists, WinDbg overwrites the existing file, unless you select the Append check box. If you specify a file name but no path, WinDbg puts the file in the default directory that you started WinDbg from.
If the Log file name box already displays a file name, you can click Close Open Log File to close the file. If you clear the Log file name box and enter a new log file name, the previous log file will be closed.
Click OK to save changes, or click Cancel to discard changes.
If you click OK when no log file name appears in the Log file name box, it has no effect. That is, WinDbg does not close a log file or open a log file.
However, if a log file is already active and you click OK without clearing its name or selecting Append, WinDbg deletes the log file and uses a new file that has the same name.