Load runner 9.1 - Uploading a file to Sharepoint using Flex 3.2

We have recorded the script using LR -VuGen for uploading a file to Sharepoint using Flex 3.2.
we are not able to view the physical path of the file while uploading a file and hence the source url is not getting recorded in LR Script and when replayed we are getting error.
When we tried to hard code the source URL in the recoded Script and execute, we are still getting the same error.
Please find the attached screenshot of the error.