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The title pretty much says it all. I am attempting to install CentOS 5.5 on Oracle VM VirtualBox. I press enter for normal installation, things start to happen and then it hangs with the above message.

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up vote 8 down vote accepted

See this ticket.

I must append kernel boot parameter nolapic or enable IO APIC in the settings of the guest

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That was the solution! I enabled IO APIC for the virtual machine and now I am installing. – Icode4food Feb 7 '11 at 19:08
nolapic strikes again. – David Mackintosh Feb 9 '11 at 4:59
Alternatively, you can turn on IO APIC in VirtualBox – Gabor Csardi Mar 19 '13 at 14:50

Choose Redhat (64 bit) from the Version pulldown of the General Settings->Basic tab screen (it defaults to Redhat) when the initial Setup is being done and the IO APIC will be enabled automatically.

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