You may see the following error while opening or using QuickBooks desktop. 

QuickBooks displays this error because it cannot access your company data file. There are several possible causes of the error.

You use a standalone computer
  • The folder where the file is saved may need additional permission
  • A 3rd party process/service from an Anti-Virus firewall may be interfering with QuickBooks
  • Your QuickBooks file may be corrupted
Your computer is connected to a network and your data file is stored on another computer
  • The network connection may be unstable (non-wired connection)
  • The folder where the file is saved may need additional permission
  • Firewall is preventing access over the network
  • Power saving mode is turned on

Resolve Connection has been lost error

Quick Tip

Tips to resolve the issue:
  • Restart Database Server Manager
  • Move the file to a different folder
  • Set Power saving option to never
Tips to prevent the issue from happening again:
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