Excel doesn't save shared workbook on nas

Hello everyone,

I have a problem with the excel's shared workbook,

on a NetApp NAS I have more shared folders, and finding the problem on only two of these

every time I try to change the .xlsx file gives me the following error, as described in this kb: http://support.microsoft.com/kb/291204,
unfortunately I have not solved the problem with this guide.

can someone help me?
thanks

greetings


PS: the environment is under the domain,

this problem was found by all users, users use excel 2010.