How to update biber in MikTeX Portable

I was working fin with MikTeX 2.9 on Windows XP until last week when I
added to my thesis few notes in polytonic Greek and acronyms with the
acro package, and since that day I can't compile anymore my thesis.

I installed TeXlive 2014 in another machine with the "surprise" to
discover that biber is in its version 1.8 and not 1.9 as was in MikTeX
2.9. This week I used a pendrive USB for load Portable MikTeX, finally
after install editors, visors and all that stuff, I tried to run my
thesis there with the surprise that the version of biber installed in
the Portable MikTeX is the 0.99d!!! a very old one.

So I wonder how to update that biber inside portable MikTeX. My first
idea is to download the last version and replace it, but I'm not sure
if it works, could someone help me?

Regards
Aradnix

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