Excel upload functionality in planning transactions - error during upload

Hi to all,

I have created a planning layout and I have generated the Excel file format, but when I am trying to upload the txt file I always receive following error:

""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

Value 000 in field "Period" is less than 1

Message no. K9019

Diagnosis

In either the initial transaction screen or within layout definition, value 000 was entered for characteristic Period.

However, the smallest valid entry is 1.

""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

Surprisingly, the upload is working perfectly when I am working on my own laptop (sapgui 7.10, excel 2007). But when I am trying to execute the upload from a customer workplace (again sapgui 7.10, excel 2007) I am always receiving the error message above. I am receiving the message independently of the planning layout I am using (I tried with many different layouts).

Does anyone know anything concerning this issue?