Formula in a macro doesnt work for Spanish Excel user

Keebellah: DV = DateValue(DayNum & " " & Mnth & " " & Yr) is the line of code that is making the macro error.

=DATEVALUE(MID(D1,FIND("\",D1)+1,FIND(" ",D1)-FIND("\",D1)-3) &" " & MID(D1,FIND(" ",D1)+1,15)&MID(D1,FIND("\",D1)-4,4))
Will always return VALUE error in any system other than English.

The problem is the system locale, it's in Spanish, and you're parsing a month string "October", which has no meaning and can't be translated into a proper month number, as the string for Month 10 is "Octubre" in Spanish.

SYSTEMLOCALE = Application.LanguageSettings.LanguageID(msoLanguageIDUI)
Spanish locale is 1033, so you could do a:
IF SYSTEMLOCALE = 1033
CHANGE MONTH STRINGS FROM ENGLISH TO SPANISH: Enero, Febrero, Marzo... an so on

Hope that helps a little.