The Office portal of DAS is available via WIPO web site at: https://www3.wipo.int/dasofficeportal.
A demo version of the DAS Office Portal, allows you to try it out before you use it for real. The demo portal is available at https://webaccess.wipo.int/dasofficeportaldemo
To use the WIPO DAS Office portal, you should first login with your WIPO account username and password as follows. 
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