I've managed to fix the issue. I needed to reactivate my product key.
Thanks
Hi,
So I originally had a custom license field as a string value, so my app was expecting a string value when I use ta.GetFeatureValue("Data Export", "").
However, I changed the field to a Date/Time type, I've redownloaded the TurboActivate.dat file and placed it in my executable folder, yet when I run the app and execute that line it is still returning the same string as previously and throws the exception that the string was not recognized as a valid datetime when I try parse as a DateTime.
Yep, and for other's reference this is covered in the custom license fields article: https://wyday.com/limelm/help/license-features/#change