Hi Trupti,
At which stage are you seeing this error. If it is at the Open Workbook then do provide the correct handle and the File Name parameter enclosed within quotes. A good way to get the correct file name is go to the location of the file and while pressing Shift, right click on the file. Now you will see an option as 'Copy as path'. This is copied along with double quotes enclosed to the path. Paste it directly into the File Name parameter without making any changes. The other thing is to make sure to use the correct Handle.