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- Uninstall and reinstall the application
- Reboot
- Check if the referenced DLL is missing or not
- Verify correct IIS settings enabled
- Windows updates are up to date
- Reset IIS
- at command line prompt running as administrator: IISReset
- Dependency Walker
- Fuslogvw
- Process Monitor
- Filters:
- Process Name = w3wp.exe
- Path ends with <name of dll>
- Helpful article
- Filters:
- Security Policies for application pool user and machine
- Local Security Policy
- gpresult /s localhost /z
- Memory and processor available
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