Dell Latitude E6420 (Early 2011) - Manual (Page 30)

6. Pull and remove the hard drive caddy away from the hard drive.
Installing the Hard Drive
1. Attach the hard drive caddy to the hard drive.
2. Tighten the screw to secure the hard-drive caddy to the hard drive.
3. Slide the hard drive into the computer.
4. Replace and tighten the screws that secure the hard drive to the computer.
5. Install the Battery .
6. Follow the procedures in After working inside your computer .
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