I am a developer and have developed several macros/functions in excel
using vba. However, when my users (non developers) try to use the
macros, they get the error "Can't find project/library". Since I
inherited some of this code, it is not using Option Explicit. After
playing around with the code, it wants me to define all the variables
first.

Also, when I use internal functions such as chr(), it wants me to
preface it with vba.chr(). I don't think I've ever had to do this
before. Is something missing on the machines where this is happening,
since it doesn't happen on my machine ?

Mark