If you facing bad pool caller then follow these steps to resolve your issue
- Identify Hardware Problems
- Run System in Safe Mode
- Reinstall the Security Software
- Start Security Scan
- Scan for Registry Errors
I also have article where you will find all the details of given steps to fix the error
Here is the link:
www.backspacetab.com/fix-bad-pool-caller-windows-8/
Best of luck