I am unable to download the macOS big sur.the installation is not getting completed

Firstly, read from this link How to upgrade to Big Sur Second - special attention to Empty Disk Space Requirements for successful installation.

There are reasons like slow internet connection over Wifi, unstable connection via Wifi or not enough empty Space.

Suggest verifying all item in linked Apple Document

Thanks for answering. I tried #1, it did download the whole 12.2GB update but it felt like the file was already on the drive, since the whole process took less than a minute. Even though the downloaded data size was showing 12.2GB the progress bar was stuck at some 90% for 5 min or so. Maybe there was some sort of file integrity check running in the background that failed because eventually the error to reappeared.

Any ideas?

I'm having the same problem, the software update download stops at more than 80% and an error box comes up "An error occurred while installing the update".

I'm trying to update from Catalina ver. 10.15.7 to the Big Sure on my MAcBookPro 2019 with 59GB free disk space. This is not the first time I'm having this issue. It also happened when I was updating to the Catalina and the one before. The difference now is that before I was always able to "manually" download the update on my drive and install the update from there. This is not available anymore with BigSure - or maybe I just can't find it?

There are 3 methods I have seen work. 1 - Directly from the Apple Apps Store and it will bring down the Full 12.22 GB installer to Applications Folder. 2 - Same method as # 1 but via Safe Boot # 3 Vis Recovery Mode and choose Reinstall macOS

As of this writing - there is no standalone update to 11.1 - do not know if that is passe or let to come with 11.2.

Best this Holiday Time and good luck

Please, go Applications Folder >> Look for an application called Install Big Sur. If it is there, drag to Trash and empty Trash. Try method #2 and let us know how it works / does not work.

Unfortunately the file is not in the Applications folder.

Option #3

Will try that and see how it goes. Thanks for helping.