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How do I correct an install and start problem

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I am running Windows 7. I installed Firefox without difficulty. All other running software including ZoneAlarm were turned off. When I tried to start Firefox I got the error message "Couldn't load XRE functions" and was unable to start the program. I uninstalled Firefox, rebooted my computer and reinstalled the software. Experienced the same problem. Any suggestions.

I am running Windows 7. I installed Firefox without difficulty. All other running software including ZoneAlarm were turned off. When I tried to start Firefox I got the error message "Couldn't load XRE functions" and was unable to start the program. I uninstalled Firefox, rebooted my computer and reinstalled the software. Experienced the same problem. Any suggestions.

Chosen solution

This is likely caused by Zone Alarm. Please try the instructions to turn off virtualization in the following support question http://support.mozilla.com/en-US/questions/880170

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Chosen Solution

This is likely caused by Zone Alarm. Please try the instructions to turn off virtualization in the following support question http://support.mozilla.com/en-US/questions/880170

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Suggestion to turn off ZoneAlarm Virtual Browser was the answer. Firefox is working well. Thanks for your help