For no apparent reason Windows started to get stuck during boot-up and at slightly different points it seems. Sometimes I get the boot animation, sometimes not. Safe mode works though, chkdsk finds no disk errors. Windows' start up repair gets stuck as well. I have a dual boot with Ubuntu and incredibly enough Ubuntu also gets stuck during booting starting at the same moment. Even booting Ubuntu from a stick gets stuck without error msg. How do I pinpoint the problem? Many thx to you all!