Just upgraded my White Macbook from 1 gig to 3 gigs RAM. I thought this would enable me to upgrade my OS from Snow Leopard to a better (newer) OS X, but was unable to download El Capitain from the App Store. How can I obtain a newer OSX?

Upgrading to Mountain Lion

To upgrade to Mountain Lion you must have Snow Leopard 10.6.8 or Lion installed. Purchase a redemption code at the Online Apple Store: OS X Mountain Lion. Mountain Lion is $19.99 plus tax. Use the code to redeem a download of Mountain Lion from the App Store. The file is quite large, over 4 GBs, so allow some time to download. It would be preferable to use Ethernet because it is nearly four times faster than wireless.

OS X Mountain Lion - System Requirements

Macs that can be upgraded to OS X Mountain Lion

1. iMac (Mid 2007 or newer) - Model Identifier 7,1 or later.

2. MacBook (Late 2008 Aluminum, or Early 2009 or newer) - Model

Identifier 5,1 or later.

3. MacBook Pro (Mid/Late 2007 or newer) - Model Identifier 3,1 or later.

4. MacBook Air (Late 2008 or newer) - Model Identifier 2,1 or later.

5. Mac mini (Early 2009 or newer) - Model Identifier 3,1 or later.

6. Mac Pro (Early 2008 or newer) - Model Identifier 3,1 or later.

7. Xserve (Early 2009) - Model Identifier 3,1 or later.

To find the model identifier open System Profiler in the Utilities' folder. It's displayed in the panel on the right.

Are my applications compatible?See App Compatibility Table - RoaringApps.

Does your computer meet the above requirements? If not, then you can only upgrade to:

Upgrading to Lion

If your computer does not meet the requirements to install Mavericks, it may still meet the requirements to install Lion.

You can purchase Lion at the Online Apple Store. The cost is $19.99 (as it was before) plus tax. It's a download. You will get an email containing a redemption code that you then use to download Lion at the Mac App Store. Save a copy of that installer to your Downloads folder because the installer deletes itself at the end of the installation.

Lion System Requirements

1. Mac computer with an Intel Core 2 Duo, Core i3, Core i5, Core i7,

or Xeon processor

2. 2GB of memory

3. OS X v10.6.6 or later (v10.6.8 recommended)

4. 7GB of available space

5. Some features require an Apple ID; terms apply.

Are my applications compatible? See App Compatibility Table - RoaringApps.

What happened when you tried to download el Capitan from the App Store? Did you get an error? If so what did the error say?

What model exactly of White Macbook do you have? Look in the Apple Menu->About This Mac section.

Upgrade to OS X El Capitan - Apple Support

If your MacBook is not eligible for El Capitan, then it won't be eligible for any other OS beyond Lion.

All OSx versions from Mountain Lion up to el Capitan have the same system requirements.