I have an Excel workbook that is updated once every morning with new data. It is then opened read only by other users to generate calculations for the remainder of the day. When I open the workbook on my machine I have UNCs in all of my Data Link fields whic is correct. When opened on one of my users machines it comes up with the drive mapping letter path.

Is there some setting that can be used to turn this off on his machine?

EDIT: I am Using Excel 2010....guess I should of put that in there!

Hi,
From your description, I notice that you have UNCs in all of my Data Link fields.
If the source data file is opened by a UNC path, the link does not revert to a mapped drive, even if a matching drive is available.
If you have both UNC and mapped drive links in the same file, and the source files are open at the same time as the destination file, only those links that match the way the file was opened will react as hyperlink. Specifically.
Please refer to the following link:
http://support.microsoft.com/kb/328440/en-us
If you need to turn off it,  you may use HYPERLINK function in Microsoft Excel.
Please refer to the following link:
http://office.microsoft.com/en-us/excel-help/hyperlink-function-HP010342583.aspx

Regards,
George.zhao