my MacBook's version is macOS high sierra and I want to update it to macOS Catalina. I downloaded the version of macOS Catalina but iam not able to install it. what should I do in this case?
MacBook Pro 13", macOS 10.13
Try deleting the app, then re-downloading the macOS Catalina installer from the App Store.
If this doesn't work, you can install the latest version of macOS using macOS Recovery without losing any data. To do this, shut down your Mac using the Apple menu in the top left corner. When turning your Mac back on, hold Option + Command + R. It is highly recommended that you use the keyboard that came with your iMac or a Wired USB keyboard to do this. Then install macOS Catalina using Internet Recovery. If you don't erase your disk (which you probably shouldn't), all of your files will still be intact. How to reinstall macOS from macOS Recovery - Apple Support
Try deleting the app, then re-downloading the macOS Catalina installer from the App Store.
If this doesn't work, you can install the latest version of macOS using macOS Recovery without losing any data. To do this, shut down your Mac using the Apple menu in the top left corner. When turning your Mac back on, hold Option + Command + R. It is highly recommended that you use the keyboard that came with your iMac or a Wired USB keyboard to do this. Then install macOS Catalina using Internet Recovery. If you don't erase your disk (which you probably shouldn't), all of your files will still be intact. How to reinstall macOS from macOS Recovery - Apple Support
What kind of message are you receiving from your Mac when trying to update? Do you have enough storage (18 GB or more) of free space on your Mac? What year was your Mac introduced? Macs introduced in 2011 or earlier aren't officially supported in macOS Catalina.
They are telling me "An error has occurred validating the installer data.The download is either damaged or incomplete". I do have a enough storage (around 90GB). My Mac was introduced in late 2013.
version update to macOS catalina
