Excel 2010 will open multiple spreadsheets as child windows within one instance of Excel, making it impossible to have two spreadsheets open on different monitors. Here’s how to fix:
HKEY_CLASSES_ROOT\Excel.Sheet.8\shell\Open
- Rename or delete the ddeexec sub-key
- Under the command sub-key:
- Modify the (default) key’s data by replacing /dde or /e with “%1″ (include quotes)
- Modify the command key’s data by replacing /dde or /e with “%1″ (include quotes)
HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\Open
Repeat the above procedure. This will cover XLSX files.