Thanks for joining the thread, Jos.

I'm here to share some additional solutions for QuickBooks Desktop's aborting issue.

Apart from setting up the time-out session of each user, you also need to consider connecting to the network using a wired connection.

This abort notification could be caused by a number of reasons. Among them are the following:

• The firewall is preventing access to the network.

• The folder where the file is saved needs additional permission.
• Power saving mode is turned on. 
• The connection error is unstable (Non-wired connection).

This program's unexpected behavior can be resolved by updating QuickBooks to its latest release.

For more troubleshooting solutions, you can read this article: Connection Has Been Lost.

To learn about the different user types and levels of access in QuickBooks, you can check out this article: Create and manage roles in QuickBooks Desktop.

Kindly post here again for any updates after contacting support. I'll be right here if you need other assistance with QuickBooks. Have a good one!