You do not need to use Set to load a public variable, just assign it like so

   myVar = "Bob"

However, you cannot reference a variable in one workbook from another book.
One way around this is to create a simple public sub in the workbook with
the variable, and access the variable from there. You then use that macro
like so

   Application.Run "FirstBook.xls"!TestVariable"

--

HTH

Bob Phillips

(remove nothere from the email address if mailing direct)

In the 2nd workbook create a reference to the 1st workbook (Tools |
References...).  Whether you need a Set or not depends on the type of
variable.

You can't use a public variable in one workbook in another workbook.  Public
means public to the project and the project is the workbook.  There are no
application level variables.  A workaround would be to put the information
in a defined name (manually it would be Insert=>Name=>Define but it can be
done in code), then get the information that way.

Now that that is said, there are two workarounds.  In the second workbook,
you can go into the VBE and in Tools=>References you can create a reference
to the first workbook.  Once created, you can use public variables and code
in the first workbook as if it were in the second workbook.   If you do
create such a reference and save the workbook so it is preserved, then
whenever you open the second workbook, the first workbook will be opened
automatically.

Another approach would be to put a function or functions in the first
workbook which can work with the public variable.  then you can call these
function using Application.Run

First workbook in a general module.

Public myvar as Variant

Public Function SetMyVar(arg1 as variant)
 On Error goto ErrHandler
 myvar = arg1
 SetMyVar = -1
 Exit Function
ErrHandler:
SetMyVar = 0
End Function

Public Function ReturnMyVar()
 ReturnMyVar = myVar
End Function

then in the second workbook

Dim res as Long
res = Application.Run("FirstBook.xls!SetMyVar",21)
if res = 0 then
  msgbox "Problems"
  exit sub
End if
msgbox "MyVar = " & Application.Run("FirstBook.xls!ReturnMyVar")