Guys, F9 or F10 don't work for me at all on my new 27" desktop. Open System Preferences > Keyboard and select the Keyboard Shortcuts tab. Select Exposé & Spaces in the left column and see if those keyboard shortcuts are checked.
Jon
macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
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