When you are in a directory and trying to save a file with a name that similar to a sub-directory, the common-dialog control thinks you want to open the sub-directory.

You can try these ideas:

1. Set the common-dialog's Filename property in the design environment to the value you want and when the common-dialog's ShowSave method is invoked, just press the OK button.

2. When the "Save file" dialog is displayed on the screen and you need to select a file name, type it with the extension of the file (ex: QWERTY2.txt) and then press the OK button.

Good Luck!!!