If the email address is greyed out. I did the following troubleshooting:

1) Enter to EDIT contractor

2) change the Social Security number to a "fake" (just one number to make sure you can correct it later) and SAVE it

3) Go back to contractor EDIT and a) correct the Social Security (to its real number) b) the E-mail section will be active and you can enter the e-mail address. Then SAVE it. 

Good luck !!! it worked for me