Quickbooks File Repair — C=0 Error
Error C=0 appears when accessing the Internet Connection Setup in QuickBooks and is usually caused by an outdated WININET.dll file on your computer. It is a Windows-component issue tied to Internet Explorer, not corruption inside your company file.
What C=0 means
WININET.dll is a Microsoft Windows programming interface that provides Internet Explorer functionality. QuickBooks uses it for its internet connection features. For Wininet to work correctly, the version of that .dll should match or be greater than the installed version of Internet Explorer. When it is out of date, accessing Internet Connection Setup can throw C=0.
Symptoms you'll typically see
C=0appears specifically when opening Internet Connection Setup.- Internet-dependent features in QuickBooks behave unreliably.
- The error follows a partial or interrupted Internet Explorer update.
Common causes
- An outdated
WININET.dllfile on the computer. - A version mismatch between
WININET.dlland the installed Internet Explorer. - A damaged or partially updated Internet Explorer installation.
What you can safely try first
- Determine which version of Internet Explorer you are running: choose About Internet Explorer from the Internet Explorer Help menu.
- Confirm the
WININET.dllversion matches or exceeds that Internet Explorer version. - Apply the latest Windows and Internet Explorer updates so the
.dllis refreshed. - Reboot after updating, then reopen Internet Connection Setup to confirm the error is gone.
When to call our team
A C=0 tied to WININET.dll is a Windows-component fix, not a data-recovery case. If, however, QuickBooks throws data errors or refuses to open your company file, the problem has moved to the .QBW itself. Our engineers can examine the file and its .TLG log and repair it when needed. We work in-house in North America, and our no-data-no-charge policy means you pay nothing unless your data is recovered.
See QuickBooks data recovery or start a recovery if your file shows signs of damage.