ctrl+alt+esc

go to the processes tab and close whatever is taking up the most memory or space on your computer.
(It'll say it next to the name of the process)
If that doesn't work then download CCleaner, and run that.
It'll help speed everything up.
here's the link.

CCleaner - Optimization and Cleaning - Free Download

---------- Post added at 11:48 PM ---------- Previous post was at 11:47 PM ----------

ctrl+alt+esc

go to the processes tab and close whatever is taking up the most memory or space on your computer.
(It'll say it next to the name of the process)
If that doesn't work then download CCleaner, and run that.
It'll help speed everything up.
here's the link.

CCleaner - Optimization and Cleaning - Free Download