What to do depends on what you've got. You don't tell much, if anything, about that. Studying the user manual and the disks that came with the machine might help.
Generally, the different options are:
1. The machine came with a 'recovery partition' you can boot from; then follow the instructions.
2. The machine came with 'recovery disks' you can boot from; then follow the instructions.
3. The machine came with instructions on how to make your own recovery disks when you first used it and you did. Then see #2.
4. Like #3, but you didn't. Then there might be an option make those disks right now. Should be in the user manual.
5. Non of the above. Then order the disks with Acer.
If you've got more details, post again for more dedicated help.
Kees
Hi, im a complete newbie to the computing industry and I bought an Acer Extensa 5220 about 2 years ago now. And im running out of disk space quickly. I would like completely wipe my C: from anything I have installed myself and hopefully reset it to how it was when I got the laptop, please help?

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