I downloaded Tex Live 2020 ISO file from CTAN mirror. I mounted the ISO file on disk D. Then I double click install-tl-windows.bat to install it. It went pretty good until the end of the installation:
Installing [3516/3518, time/total: 01:58:09/01:58:12]: zwgetfdate [242k]
Installing [3517/3518, time/total: 01:58:11/01:58:13]: zwpagelayout [630k]
Installing [3518/3518, time/total: 01:58:14/01:58:15]: zxjafont [181k]
Retrying to install: gregoriotex.win32 [274k]
TLUtils::untar: D:\tlpkg\installer\tar.exe xmf C:\Users\shuaiy\AppData\Local\Temp\gFu3Ujnkip\VKOEdiPsuX/gregoriotex.win32.r53994.tar failed (in C:/texlive/2020)
TLPDB::_install_package: untar failed
Installation failed.
Rerunning the installer will try to restart the installation.
I tried 2 times, all give me the same error. From above error message, it seems installer was trying to untar something by calling tar.exe from mounted disk D. I navigate to D:\tlpkg\installer\ in Cmd, and calling tar.exe xmf to test. And it gives:
D:\tlpkg\installer>tar.exe xmf
tar: option requires an argument -- f
Try `tar --help' for more information.
BTW, I do find another version of tar.exe on my computer located at C:\Windows\System32 folder. This version of tar.exe seems OK with the argument -f.
Now I'm confused which step went wrong. Somebody please help me out.
[Solution]: issue fixed by using latest install-tl-windows.exe found in https:///CTAN/systems/texlive/tlnet/ directory, rather than using huge texlive2020-20200406.iso file.
Thank everyone for helping me!