In case of being CAS (AV ČR) employee, VERSO credentials are all you need to log in – see below. http://metavo.metacentrum.cz/cs/application/index.html

Scroll down, until you find your Institution (ÚŽFG as an example here).

Application form follows – fill it in and submit.

A confirmation email arrived:

děkujeme Vám za registraci do virtuální organizace MetaCentrum. …
O schválení nebo zamítnutí přihlášky budete informován(a) dalším mailem.

(whad have I done last year) http://eis.cas.cz/

I have tried it by Personal number – it is on payroll and on confirmed travell orders, or call Irena. but finally I retrieved it through my email addres.

Click here (do not “open in new tab”)

Here I entered my Muni email… firstly it complained several times something about “address is not in database”, but then it yielded… I don't remember for sure and I don't want to try it because I don't want to block myself… Maybe it showed something about different email address or something…, nevertheless an email arrived promptly and after clicking, a password appeared and I printed it to PDF and saved.