Inconsistent FileLoad error

Hi team, I'm implementing an webapp and experiencing an error as below.
BAS-010014 Cannot open file '/usr/local/neolane/nl6/var/SAS360/survey_data/655708__questionList.xml' with read access (errno=2, No such file or directory)
The error happens every other time when I load. (whenever I enter the link, it loads, but after I reload from the web browser it shows the error page showing the error page. when I reload once more then it loads again and it repeats.)

I tried checking the web server log and the log stacks only when the loading was successful. 
I'm assuming the file does not exist in one of the two application servers. the file is generated from a table by a workflow.
could anyone give any suggestions on this?