Which of these error message should I use for my add/edit user form.
(Although I am over thinking this)
I have various forms around the system where assets can be assigned to specific users. When assigning assets they can leave the firstname and lastname blank meaning that the asset is assigned to specific department, If they enter an e-mail address they need to enter firstname and lastname.
Must enter the firstname and lastname with an e-mail address
Must enter the first and lastname with an e-mail address
Must enter the firstname with an e-mail address
Must enter the lastname with an e-mail address [seperate lines]
Must enter the first and lastname