Jura X90 runs dry after long standing time

Hello everyone,
I have about 10 (!) Years ago bought a commercially used Jura impressa X90 and immediately given into the maintenance. When it came back with several spare parts for about 200 €, I mothballed it as a "replacement machine" (wrapped in foil in the basement), because I still had a well-functioning machine. Now I want to put it into operation after all these years and everything seems to work so far mechanically/electrically, but not a drop of water seems to arrive in the machine: After the first "fill system / press steam" the pump works extremely loud (probably because it runs dry), no drop ever comes out of any spout, not even into the drip tray. At some point the machine shows ready, but instead of making coffee dry ground powder comes into the marc container, the machine shows "fill system / press steam" again and the game starts all over again. Haven't opened the Jura yet, just checked the tank water drain, it works great. My question: what could be the cause and where do I start and how to get the machine going?
Many thanks in advance,
greetings
,

Achim

Did water come out of the hot water outlet before it went to Ready?
I think the pump needs to be force filled after the long idle time. I use a large syringe that I connect to the pump inlet.
To do this, however, you need to remove the rear panel.

Thank you, Schlawi!

I did so - now the pump is "nice and quiet" because filled with water, but coffee continues not to come. Somewhere the system is clogged.... The pump pumps against some resistance and if one then breaks off, the whole system is mighty under pressure. I have on the search times the vertical upward departing hose (branch before the pressure valve) pulled off - there came steam like an explosion, but only very briefly. obviously few drops of water were ultra-high there! So in short: Pump pumps, heating unit heats, grinder grinds, but no water arrives at the ground coffee and also not elsewhere. Also hot water, rinsing and steam draw do not bring a drop of water to the light of day ... the pump pumps to the Abwinken. Machine then reports again after unsuccessful coffee withdrawal: Fill system / press steam withdrawal....

What to do?

You have to look where the blockage is. Check the lines piece by piece. Also check the solenoid valves whether they switch. It is possible that one is stuck due to the long service life.