Load Runner has stopped working error in LR 12.02 Controller

Hi,

I am running few scripts in controller, of which for one of the script I see "LR has stopped working error". I have assigned 50 vusers, it runs smooth till 8 users ....above 8 pops up error...and remaining goes in to error. But 8 will run smooth...

Once I select OK or cancel button, all the users assigned to that script goes into errors.

Troubleshoot:

1. Tried with different LG machines (LG with Win 7 and Win 2012 R2 server machines)

2. Tried with different Controller Version (12.02 and 11.04)

3. Re-Recorded the same script again (Thought script corrupt), still errors

3. Unchecked UAC and DEP settings..still same error..

Machine and Tool Specs:

LR 12.02 on win 7 OS, Protocol: Web(Http/Html), LG: Win7 and Win 2012 R2.

Thanks,

Prasanna Kumar