Computer?
Umm..keyboard...or monitor...or tower/HD? Whatever, here's a bit of help, but sometimes the cure is as bad as the problem. If it's the keyboard I'd ante up another $5-$10 and get a new one or live with the red (pretend you wanted it that way...lol..although green would be better in your case)
Twink (Whiteout) (Liquid Paper) (Liquid Correction Fluid)
Purchase some Spray & Wipe from your supermarket, and use concentrated on the stain. Most Spray & Wipe formula’s contain a solvent which will dissolve the liquid paper. OR Try a little gasoline on the stain, with some good absorbent paper or old cloth behind it. Then use some dishwash liquid or a good quality laundry liquid to wash out the gasoline. OR Purchase some xylene, or toluene, these are some of the solvents used in making the stuff. Use as if using the gasoline. These are stocked by gasoline companies and you may be able to request a small sample. Always test an inconspicuous piece of material before proceeding, or if you're working on a material like your tower case, try a small spot and let it dry to see the result..... Q