We know it can be frustrating to reinstall your paid QuickBooks Desktop and then run into registration problems, especially with the 30-day time limit, diamondraught.

QuickBooks Desktop 2015 is an older version that has been discontinued. You can still use it to view past data, but it no longer gets updates or support. The registration problems you are seeing are likely because support for older versions has ended, which makes it harder to register or use the software.

Since June 30, 2023, QuickBooks Desktop is no longer supported in the UK, and even UK customers do not receive updates or help. You might consider switching to QuickBooks Online, which stores your files in the cloud so you can access and update them whenever you need. For more help, please visit the QuickBooks Desktop discontinuation support page.

In addition, here's an article to gain insights on QBO's workflow and how you can optimize your business processes: Get started with QuickBooks Online.

Please revisit this post if you have more questions about managing your business in QuickBooks Desktop.