When using a machine where 2 MS Excel versions (for example 2003 and 2013) are installed, the oldest Excel version (2003) is executed by default when opening a report from Web Portal
It is not recommended to install two Excel versions on the same machine.
To force the machine to work with another version of Excel (in this example Excel 2013 rather than Excel 2003) you must reset your file association from "Excel 2003" to "Excel 2013" :
You might have to designate a full path to excel.exe for "Office 2013".
In that case:
- Start>Run "C:\your path to\officexx\excel.exe" /regserver>OK.