Macro to send emails based on date

I have been working on creating a macro that would automatically send an email based on the date in a specific column. After trying myself unsuccessfully I began searching online and found this post: http://forums.techguy.org/business-a...-due-date.html. Here you can find pretty much the exact code I was looking for written by XCubed. I adopted that code to fit my worksheet and was able to get almost everything to work (Example Workbook.xlsm). The problem I am running into is that the column I am referencing does not always have a date in it. Sometimes this column will have "TBD" or "ASAP" written in it and there is also blank rows used as separators. I am trying to find a way to use the same macro and include some sort of logical requirement that will run the code without getting an error. Basically I want it to ignore cells that aren't dates (both text and blank cells) and move on to the next row. Is there a way to accomplish that?