Hi, MB pro mid 2010, A1278 2.66 ghz core 2 duo 8gb ram, 1tb hd (not original 320gb, I updated 2014 with a seagate 1TB hybrid ssd/spinning disk) s/nr W80193DTATD Only works when connected to power cable as battery is dead and wont charge. In anticipation of trying to sell my old macbook pro, (not worth a lot but needs must) I went through a series of OS updates to get it to 10.12.6 I then disabled icloud/itunes/imessage etc as advised elsewhere.. I then initiated HD erase in disk utility. I've now hit a problem in that I can't seem to reinstall macOS.... when i follow the prompts i get a screen which says the recovery disk is locked. image attached... So I can't proceed. If i go back to DiskUtilty screen it shows 2 sections: Internal and Disk images.... I was wondering if I need to do something there...if so what.....? images attached... Suggestions / advice appreciated..