mauig1001 error

I recently uploaded this to google play and everything compiled correctly. I am suddenly getting a number of errors, the primary being the following:
MAUIG1001 An error occured while parsing Xaml: Name cannot begin with the '<' character, hexadecimal value 0x3C. Line 21, position 17.. DartsPro XXXXXXX\DartsPro\CSC 1 In the project file the referenced character doesn't exist.