How come QuickBooks is not opening on my computer

There are times that local internet cache files stored in the system can cause unexpected behavior in the product, leighanne4119.  

As mention by Fiat  Lux - ASIA, let's signing in to QBSE using a private or incognito window. This mode doesn't use the existing cache data and helps us confirm browser-related issues.

Here's how: 

• For Google Chrome browser: Ctrl + Shift + N
• For Mozilla Firefox browser: Ctrl + Shift + P
• For Safari browser: Command + Option + P 

If it works, go back to your regular browser and clear the cache to delete those temporarily stored files and browsing history. The overtime collection of data can create corruption, however, removing this should fix the issue. You can also use other supported, up-to-date browsers to roll out the possibility of a browser-related issue.    

Don't hesitate to get back here and reply to me if you have follow-up questions. You can also post new questions if you need anything else in the future. Stay safe!