how to download OS X El Capitan for MacBook Pro A1278 I have a Macbook Pro A1278 with a dead hard drive.  I have put a new hard drive in it and now need to figure out how to get my hands on the os.  Does anyone know if it is possible to still download OS X El Capitan?  If so, how?
Apple has a page How to get old versions of macOS which includes a link to download OS X El Capitan 10.11.
The next question is going to be how to make a bootable installer. Do you have another Mac available?
If so, DiskMaker X would be the place that I would start.