Does sqlserveragent account needs full control on a fileshare to modify a excel ?

I have a SSIS package which formats data using c# code in ssis script task .I can run it using sqlserveragent account which hasfull control permissions on the file share folder in DEV but in QA when I try to run I get error innovation error at c#\script task.

The sqlserveragent account has modify permissions set on the file share folder in QA 

The flow of ssis package is as follows.

Prep data and dump it in a sql table and then use the table to write data in excel over a oledb connection . Once the data write is done format using c# /script task . 

SSIS 2014 and SQL server 2014.

Excel format- .xls