Hi there! I understand you're encountering an error message while searching for flights on multiple days using the Virgin Atlantic app. To assist you better, could you please share what the exact error message says? Also, are you using the app on your Windows 10 device via a browser or as a native app?

Meanwhile, I'll guide you through some common steps to try and resolve this:

1. Restart the app or browser: Sometimes, simply closing and reopening the app or your browser can clear temporary glitches.

2. Clear cache and cookies: Since you're on Windows 10 WebKit-based browser, clearing browser cache and cookies can help remove any corrupted temporary data that might cause errors.

3. Try searching from the start: Occasionally, fares or availability can change during the booking process, causing errors if mid-search data is outdated. Starting a fresh search might help1.

4. Use Incognito or Private mode: This can bypass browser extensions or cached data that interfere with the search.

5. Check your internet connection: A stable connection ensures proper communication with the service.

6. Update the app or browser: Make sure your app or browser is the latest version.

If you've tried these already, let me know which ones and what the exact error message says. That way, I can guide you with more specific steps or check if there's an ongoing issue with our system.