Type Mismatch Error IF statement

I am trying to make a 'Sales Page' where the user can enter in details of a sale for each day. I am using a user form for it and i am trying to make it that when you enter the day, if it is incorrect then display a message box and don't run the rest of the function. Anyway, i keep getting the type mismatch error on this part of the code and i don't know why

If salday <> "Monday" _ Or "Tuesday" _ Or "Wednesday" _ Or "Thursday" _ Or "Friday" _ Or "Saturday" _ Or "Sunday" Then MsgBox "Incorrect Day. Please make sure you are using capitals!" Else

If anyone could help that would be great :D