ExpressCache service is running , caching is enabled , and the used portion is 12-15GB.
So you gives me this idea:
stopping, then restarting the ExpressCache service and after that, eccmd-info runs correctly;
since yesterday, with no more problem.
NB : before stop/restart service, I have uninstal/reboot/instal a fresh unloaded version of ExpressCacheSetup (same version),
but the problem was not resolved.
Maybe reinstal and restart has correct this problem, who knows ?
Once more, I thank you for your good advice.
Phil