The Office Web Components (OWC) are a set of ActiveX controls that provide four principal components: Spreadsheet, Chart, PivotTable, and Data Source Control (DSC).
With no regrets: The Office Web Components are being discontinued because Microsoft needed a more flexible technology to help customers address the following challenges they faced with OWC
- A server-side Excel calculation engine
- Greater parity with Excel when worksheets are delivered over the Web
- The ability to enable spreadsheets to be more scalable and stable when loaded onto a server
- Improved security
- The ability to perform more detailed analysis to improve overall business intelligence.
About support of previous versions:

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