MICR Line Issue

I am setting up a the check layout in AX 2012 and hit an error when filling in the MICR line.  I am attempting to put in an MICR line that looks similar to this c%1c a#########a#### ######c , but when I click off the field it gives me this error (MICR line c%1c a#########a#### ######c contains illegal characters) and erases my MICR line. 

Any help with resolving this issue would be much appreciated.

Thanks,

Jeff