If you have recently edited your configuration file, a simple typo or missing tag can cause the loader to fail. Structure Check
The error indicates that the TecDoc client application cannot read or access its core configuration files—usually TecDocConfig.xml , Database.config , or related .ini files. These files store: tecdoc loading data failed check the configuration file
Right-click the TecDoc icon and select "Run as Administrator" to rule out permission issues. If you have recently edited your configuration file,
Ensure that port 1433 (default for SQL) is open in your Windows Firewall. tecdoc loading data failed check the configuration file