An ODC - Office Data Connection File is an information file created by Excel in Microsoft Office. The file contains links between the Excel spreadsheet and external data sources.
During the creation of a spreadsheet in Excel many external data sources as well as data queries may be used. The ODC file keeps track of the information to maintain the connection between the spreadsheet and external data with connection strings, connection information and data query information when the spreadsheet is closed.
The ODC file information is quite useful to allow the spreadsheet to update existing data by reusing query and connection information it has stored. The files are created with the Data Connection Wizard in Excel, the wizard will generate HTML and XML segments to store the connection information. This storage format does allow the viewing of the ODC file using a web browser such as Internet Explorer, Firefox or Chrome.
To view existing connections in an open spreadsheet by selecting Data, then Connections.