Hi All Would appreciate any advice as I am having trouble with my Macbook Pro 15 2009/2010 model (black keys). A few months back I had the battery changed at a non Apple retailer (who lives in a different city so cant take it back). It then worked fine. Last month I upgraded my Macbook e.g. Ram to 8GB, Mem to 1tb and the store (a different one to who changed battery) also upgraded to Mountain Lion operating system. Last night i started to get the Service Battery alert in the indicator menu at the top...and the battery has suddenly started draining quick!! I was wondering this time i cant afford to take it into a store, but can i change it myself as its all built in? I have no IT knowledge. Where is the best place to buy the battery in the UK? Is this website/guide good? http://www.ifixit.com/Guide/MacBook+Pro+15-Inch+Unibody+Mid+2010+Battery+Replacement/3024 many thanks in advance!!