Ubuntu Guest starts but upon login, it aborts

[GVVM]

I have a serious issue on a guest vm that I use for some very important work. Need help getting it running again by Monday.

Thanks in advance.

Host is ubuntu (16.10 Xenial), Guest is Ubuntu (18.10)
They were all working fine until I decided to upgrade from Virtualboc 6.1.2 to 6.1.10.

Upgrade went without issues.

I applied the extension pack on Host --------- OK
I applied guest additions on the Guest VM (I think I used the 6.1.10 guest additions download)

When I start the guest VM, it starts ok, but as soon as I login as any user, it aborts.

Please help.

-

[GVVM]

I couldn''t afford to troubleshoot further. So I downgraded to 6.0.22 and it is working fine.

I have an issue though, I am unable to copy / paste between 2 different ubuntu VMs. This is such a handicap for me.

Any ideas?

Host to Guest works between the host and the 2 different ubuntu VMs however.

Thanks