[tex-live] Problem with installation: cannot determine release!

[Norbert Preining]

> If I launch tlmgr update --all in the command prompt, I get a series of
> invisible characters followed by:
> 
> at C:/texlive/2017/tlpkg/TeXLive/TLPOBJ.pm line 103, <TMP> line 1.

It seems that your files got corrupted, due to whatever reason.

I suggest getting the 
  update-tlmgr-latest.exe
from
  http://mirror.ctan.org/systems/texlive/tlnet/update-tlmgr-latest.exe
and run it. I hopefully will fix your system.

If not, please report back.

Norbert

--
PREINING Norbert                               http://www.preining.info
Accelia Inc.     +    JAIST     +    TeX Live     +    Debian Developer
GPG: 0x860CDC13   fp: F7D8 A928 26E3 16A1 9FA0 ACF0 6CAC A448 860C DC13