If QuickBooks won’t open, it could be due to a variety of factors. However, the following are a handful of them:

It's probable that the company name is lengthier than necessary.

The QBWUSER.INI file is corrupted or broken.

There are issues with the hard drive.

QuickBooks Desktop has been installed wrongly, resulting in corrupted application files.

The Windows operating system has been infiltrated.

During the installation procedure, there was an error.