Some displays have no Wi-Fi and are only connected for updates via manual hotspot.
If I schedule two layouts in the calendar, the second layout, which follows later, is not displayed and instead the default layout. It looks like XIBO has not downloaded the second layout, which follows later after the first layout, and there is no internet at the time of the change. I would be happy about a solution.
Greetings Mark
The Players download 2 days worth of content and schedule by default.
If your change occurs after that 2 day window, the Player will run out of content to show and will show the default layout in that case.
You can increase the amount of schedule and content that is sent down in the CMS settings (Required Files Lookahead) but keep in mind calculating that is expensive for large periods so it will increase your CMS load.
ok thanks, I found the setting. I tried to change it to 1 year and now i cannot save the settings any longer.
If you need the debuggin files. please let me now.
1 year is far too long.
You might increase it to a few days, or maybe even a week, but longer that that will be a problem.
You need to put the time you want in seconds - so a week would be 604800
ok, but i have not a lot of changes, only one in a month may be and the traffic should not that much. But now after trying to put in a year in seconds “unexpected error” is coming always, also when i am put in 2 days only. 
You have any suggestion… because i cannot save anything in the settings anymore.
You may get away with a higher value then, but in the general, it’s not designed to cope with very large values there.
Try refreshing the page and entering the new value.
Failing that you’ll need to directly edit it in the database.
update setting set value="604800" where setting="REQUIRED_FILES_LOOKAHEAD";ok, i did it already.
mmhh but some displays has no internet connection for may be 2 month but in between there is a change of layouts.