Cannot find TeX Live root using kpsewhich, when updating MacTeX [duplicate]

I was trying to update my MacTeX this afternoon. However, TeX Live Utility complained that it couldn't find TeX Live root using `kpsewhich --var-value=SELFAUTOPARENT`. I checked this in the Terminal, and `kpsewhich` worked well. (see the screenshot below) I had also checked other mirrors of CTAN, but the problem went on.

System version:

• Mac OS X: 10.9.5
• MacTeX: 2014

Any clues would be appreciated.

marked as duplicate by Joseph Wright♦Dec 27 '14 at 10:13

• Does `sudo tlmgr update --self` at the Terminal help? If so, this is a 'known issue'. – Joseph Wright Dec 27 '14 at 10:02