problema na instalacao do Ubuntu 21.04

Ola,
fiz a instalacao do Ubuntu 21.04 atraves do pendrive.
agora nao consigo iniciar. Tem esta msg:
Failed to set MokList XRT: out of resources
Could not create MokListXRT: Out of Resources
Failed to set MokList XRT: out of resources
Could not create MokListXRT: Out of Resources
Something has gone seriously wrong: import_mok_state() failed: out of resources

apos alguns segundos a maquina desliga.
tenho um notebook dell vostro com intel i5 de 2011

grato

Aqui parece ter a solução: https://askubuntu.com/questions/1333492/21-04-uefi-boot-fails-could-not-create-moklistxrt-out-of-res...