how to UNLOCK a DRM protected PDF temporarily

Hello,

I would like to read my DRM protected PDF not with ADE reader, but with an external PDF reader. When I try to open my PDF I am asked to enter an UNLOCK password (see screenshot). I do not want to DeDRM, I just want to read my PDF with a non ADE.

I tried the password of my Adobe login, but with no success. Do I have to enter a certain combination of Adobe-ID/password? Any idea?

Thank you in advance