Qb desktop to qb online, did not transfer all data (old P

I know this may sound uneasy, and I can help share information about transferring your data to QuickBooks Online (QBO) seamlessly, @drjames.

When the file is too large, this may be the reason why we're unable to transfer all the data. In this case, you can minimize your file by utilizing Condense tool in QuickBooks Desktop (QBDT) to compress your company file size and import them to QBO. You can follow the steps added in this article: Condense your QuickBooks Desktop file for import to QuickBooks Online.

In addition, it seems that you inquired about payroll in your previous posts. If that's all about it, some payroll information doesn’t move because QBDT has more payroll features. In this case, you may need to enter the employee data manually using the most recent W-4 form. To fix this, feel free to follow these steps:

1. Go to Payroll or Workers.
2. Click the Employees tab. 
3. Select an employee to open their profile.
4. Click the pencil icon beside Pay. 
5. In section 2, click the pencil icon again.
6. Enter their recent W-4 data. 
7. Click Done. 

If you need to retrieve your employees' 2020 annual W-2 or W-4 data for references, I suggest reopening your QuickBooks Desktop file. 

Wanted to know more about the import limits? Continue reading this article for your needs: Learn how features and data move from QuickBooks Desktop to QuickBooks Online.

Import something else aside from payroll? Please check this article for a guide on how to fix them. 

Get back to me if you have any other questions about migrating your data. Anytime I can help you here. Keep safe, and thank you for choosing QuickBooks!

@drjames 

What kind of data do you need to migrate? You may consider to purchase a 3rd party service to convert data including certain data types (e.g attachments, multi currency, estimates)