Ankita- This article should provide you some insights,
Things to keep in mind-
1) The Excelworkbook's name shouldn't change
2) data structure (number of columns and column names) shouldn't change
3) Ensure that Tableau Server has access to folder where the Excel workbook is located. Use UNC path to specify folder location.
Hope this helps.
Thankyou for the quick reply shivram. But is the article above applicable to extract connection for publishing to "Tableau Online"
And if i specify the unc path in tableau desktop and on Tableau online if the same source excel is placed in some other folder then should the connection again be edited on Tableau online?
Ankita- Sorry, disregard my previous reply, I mistook it for Server. Looks like in your case Tableau Bridge is the only option to refresh Excel data in Tableau Online, unless someone else have a work around for this. I will let others pick this up.