When getting error

Loading xenblk.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/xenblk.ko': -1 Operation not permitted
Loading ehci-hcd.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/ehci-hcd.ko': -1 Operation not permitted
Loading ohci-hcd.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/ohci-hcd.ko': -1 Operation not permitted
Loading uhci-hcd.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/uhci-hcd.ko': -1 Operation not permitted
Loading jbd.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/jbd.ko': -1 Operation not permitted
Loading ext3.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/ext3.ko': -1 Operation not permitted
Loading dm-mem-cache.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/dm-mem-cache.ko': -1 Operation not permitted
Loading dm-mod.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/dm-mod.ko': -1 Operation not permitted
Loading dm-log.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/dm-log.ko': -1 Operation not permitted
Loading dm-region_hash.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/dm-region_hash.ko': -1 Operation not permitted
Loading dm-message.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/dm-message.ko': -1 Operation not permitted
Loading dm-raid45.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/dm-raid45.ko': -1 Operation not permitted
Loading xennet.ko module
ksign: module signed with unknown public key
- signature keyid: 99a6f9685d38f58d ver=3
insmod: error inserting '/lib/xennet.ko': -1 Operation not permitted
Scanning and configuring dmraid supported devices
Creating root device.
Mounting root filesystem.
mount: could not find filesystem '/dev/root'
Setting up other filesystems.

Try to rebuild initrd for VM (it also forces resymlinking of kernel in use):

php /usr/local/solusvm/includes/xenkernel.php