Textify is designed to allow you to copy text from a dialogue box.

This tool is perfect for extracting that otherwise un-extractable text from a dialogue box. Textify comes in handy when you need to research a specific warning from a popup box, for instance, and want to do it fast and easy without retyping the entire bit of text.

Simply point your mouse over the text, click the mouse shortcut (Shift + Middle click by default), and get a selectable view of the text - easy as that.

Textify can also be launched with a hidden window by using the -hidewnd command-line switch.

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Version History for Textify:
http://rammichael.com/downloads/textify_setup.exe?changelog