You will see this warning messages If you have installed virtualizor on the custom OVH kernel, however we have tested virtualizor on the OVH's custom kernel and it seems to be working fine.
We have also provided a patch to many of our users who have installed virtualizor on OVH's kernel to hide this warning/error messages displayed in virtualizor.
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2. The primary storage could not be found
This is not a bug, but if you have not added any storage on the panel or not defined any storage as primary then this error will be displayed.