Hi there,
There are several reasons why a VM might be shown as invalid, you could try removing it from the inventory (right-click, remove from inventory) then re-adding it (browse the datastore where the VM files live, right-click the .vmx file and choose add to inventory).
Otherwise have a look through this KB to see which resolution would be relevant to yourself...
kb.vmware.com/kb/1003742
Hope this helps
vM
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VCAP-DCD / VCAP-DCA / VCP-CLOUD / VCP-DT / VCP5 / VCP4
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