Andahochdrei

I got troubles with my UM5 after swiching on. The Display starts and first it looks normal but then it get stuck and keeps booting for houres. There is no way to enter the display any way (have a look on the attached picture). Network access via „Digital Factory“ works well without any troubles or error reports. Printer can even print if i reprent a file via „Digital Factory“. Somebody which can help me with this? - many thanks in advance! Simon