apple update corrupted when downloaded and won't install, what now?

If you get a corrupted message...

Naw, not damaged, it's just that you have an old copy already in Applications.

Trash the Install MacsOS *******.app in Applications then a new copy more recent version can be downloaded.

Sorry you're having a problem. I think I can offer some useful information. First , you should only use Safari to do any downloads, not Firefox. Updates and upgrades should normally take no longer than an hour to download, plus maybe another 45 minutes to install. What often happens is that a person attempts to do their download via a wireless (Wi-Fi) connection. This is simply too much data for wireless. What results is that the data is either incomplete or is corrupted and won't load. I recommend that you move the download corrupted file to the trash and do another download with a wired ethernet connection to the modem/router. If necessary, you may have to temporarily move the computer. If this is not possible, then be prepared to have to do multiple downloads until you get a clean one that works. I hope this is helpful. Good luck.

Ronasara wrote:

What often happens is that a person attempts to do their download via a wireless (Wi-Fi) connection. This is simply too much data for wireless. What results is that the data is either incomplete or is corrupted and won't load.

FWIW, that's simply not the case. I have 5 Macs that are always upgraded via WiFi and I've never had a corrupted download. That doesn't include our 4 iPads and 2 iPhones, also upgraded by WiFi.

I believe you and accept what you say. I offered general information which is often true for many people who have download problems on this forum. I do not suggest that this will always be the case, but corruption does occur. You might tell us what specifically is occurring. What message are you getting?

I believe you missed the point. Some people do have a corrupted download. I don't and of course I get no message because the downloads are successful. It has nothing to do with "too much data for wireless".

Delete the installer from the Applications folder then try again while in Safe Mode.

How to use safe mode on your Mac - Apple Support

Any luck there?