Hello there, alweigand.

We recently updated and archived some articles, and that's the reason why you can't open the link. I've got the updated link where you can see the solutions on how to fix this error. 

Before you begin, please make sure to update your QuickBooks to the latest release. Then, for the first solution you can use the QuickBooks File Doctor. This helps resolved damage QuickBooks components.

You can also check this article for the other solutions: Error -6000.

Please let me know if you need more help with QuickBooks. Thanks.