Hi! I understand that your Norton Private Browser is closing unexpectedly whenever you try to open a private mode window. Let's work together to figure this out.

To start, could you confirm if the browser crashes immediately after selecting private mode, or does it happen after a few seconds? Also, have you noticed if this problem started after any recent updates or changes to your system or the browser? This info will help me guide you better.

Meanwhile, here are some steps you can try that often resolve such crashes:

1. Repair Norton Private Browser: Sometimes, files can get corrupted. You can repair the browser without deleting your browsing data:
- Go to your Windows Control Panel > Programs > Programs and Features.
- Locate Norton Private Browser in the list.
- Click on it and select 'Repair'.
- Make sure to untick the box that says "Also delete your browsing data" so your data stays safe.
- Proceed with the repair and wait for it to complete.

2. Clear Cache and Cookies (without data loss):
- Open Norton Private Browser.
- Go to the menu (three dots or lines, usually top-right).
- Find the option for privacy or history and clear cache and cookies, but do not delete saved passwords or site data.

3. Reset Browser Settings:
- In Norton Private Browser settings, look for an option to 'Reset Settings' or 'Restore Defaults'.
- This can fix misconfigurations causing crashes.

4. Restart your computer after these steps and try opening private mode again.

If you've already tried any of these, please let me know so I can suggest some advanced options for you.

Are you comfortable performing these steps? If so, please let me know how it goes or if any part needs more detailed guidance.