New Post: A process serving application pool 'DefaultAppPool' suffered a fatal communication error with the Windows Process Activation Service. The process id was 'xxxx'. The data field contains the error number.

Hello Everyone,

I have spent the better portion of last 2 days trying to resolve this issue to no avail. I thought now would be a good time to look for help and hence i am here:

Objective
Trying to execute a R script with C#.NET website that allows users to enter input and training files (csv) and spits out a csv file.

Progress
The website is fully functional on my local instance on Visual Studio 2010

Issue
Post deployment on IIS 7.5, the application accepts the input and training files and continues executing indefinitely.

System Configuration
Windows 7 64 bit (16 GB RAM - not more than 5 GB utilized at any point)
R 3.2.2
IIS 7.5

Diagnostics Steps Taken

1. I checked the event viewer and found a WAS warning that happens every time (unaccompanied by error). The warning says -
   A process serving application pool 'DefaultAppPool' suffered a fatal communication error with the Windows Process Activation Service. The process id was 'xxxx'. The data field contains the error number.
   
2. I also used DebugDiag for Windows and can see that w3wp.exe is closing at this time ([9/22/2015 1:07:16 PM] Process Exited: Process Name - w3wp.exe Process ID - 9552 Web application pool name - DefaultAppPool) but i am unable to find out why
   

Resolutions Attempted

1. Disabled Rapid Fail Protection in application pool
2. Enabled 32-bit applications in application pool
3. Tried to run application with smaller input files (This works. Code is able to run for CSV file with 10 rows. Current file is 1200 rows)
   

Possible Issue
Since point 3 above worked i suspect it is some kind of stack/buffer overflow but i am unable to pin-point or resolve it

Will deeply appreciate any direction you can provide.

Thanks,
Rahul