Error1004 using Shapes.Range().Align

Hi Forum
i have a big problem with the Align-Comand,for rearranging the Elements of the Shapes-Collection.
the above Syntax works fine on my system , but the colleagues in italy get the 1004-runtime-error
and i absolutly ran out of ideas why the codeline fails.
the images named in strPicName and strPicAlign are existing

what else is important befor using the Align-Command?
and are there any local Excel-settings for "error-tolerancy" or something?
any ideas? many thanks
Juergen

Workbooks(1).Sheets("Sheet1").Shapes.Range(Array(strPicName, strPicAlign)).Align msoAlignRights, False