I like it! But, now I have an embarrasing development. The textbox value could also be populated using the GETDIR function, so there may not be any KeyPress events fired. Sorry...

>Well, making it more complicated just so not to use variables <g>
>
>

>loForm			= Createobject('myForm')
>loForm.Show(1)
>
>define class myForm as Form
>	add object myTextBox as Textbox
>
>	procedure myTextBox.KeyPress(nKeyCode, nShiftAltCtrl)
>
>		nodefault
>		if nKeyCode # 92 or At('\', this.Value) = 0
>			Dodefault(nKeyCode, nShiftAltCtrl)				
>			if ((nKeyCode = 92) or (nKeyCode = 127 and substr(this.Value, this.SelStart, 1) == '\' and substr(this.Value, this.SelStart - 1, 2) # '\\')) and nShiftAltCtrl = 0
>				Dodefault(nKeyCode, nShiftAltCtrl)
>			endif
>		endif
>
>	endproc
>
>enddefine
>

>
>[Update] By the way, I realize that you can still press DEL or select text and then overwrite/delete, but do not feel like adding more code, after all this might not even be what Jay needs, maybe I completely misunderstood him.