Excel is slow while copying and pasting data

 This steps give solution for " Microsoft Excel is slow while copying and pasting data "

The original post was originally written for Excel 2003. If you’re running 2008, here are the steps you need to follow:

1. In Excel, click the Microsoft Office Button (in the top left), click Excel Options (at the bottom of the menu box on the right), click the Advanced category, and then under the General section, clear the Ignore other applications that use Dynamic Data Exchange (DDE) check box.
2. In Windows, open a command prompt: Start > Run will get you the run dialog box. Then enter “cmd”
3. Navigate to the directory of your Excel installation. On my machine that is C:\Program Files\Microsoft Office\Office12
4. Enter this command: excel.exe /unregserver
5. then enter this command: excel.exe /regserver

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