My Macbook Pro is running on 10.9.5, but says there are no updates to install. I know the High Sierra OS is on 10.13.5, and when I click on it in the App Store, it says it's installed. How do I fix this?
MacBook Pro, OS X Mavericks (10.9.5), 2013 Macbook Pro
It's possible that it was downloaded but not installed? Look in Applications for "Install OS High Sierra" and if it is there double-click to being the install.
There are no more updates for 10.9.5. There are "upgrades." Upgrades are not the same as "updates." You can upgrade to High Sierra: How to download macOS High Sierra.
Can't Update to High Sierra OS
