why is quickbooks giving me an error message of nd file? ND and . TLG files are part of your QuickBooks files. These are configuration files that allow QuickBooks to access a company file in a network or multi-user environment. If these files are corrupted or damaged, you'll see these errors when you open your QuickBooks files. As you can reach us at.Quickbooks Customer Service+1 866-669-5068,NJ.