Hi ,
Please check the compatibility matrix
VMware Product Interoperability Matrixes
vCentere upgrade reference # vSphere 6.0 Documentation Center
Also refer # “Internal error occurs during Export of VMware vCenter Inventory Service” error when upgrading from ...
you can verify the logs , if the error is looks similar ten try that solution
Also you may update to 5.5 then from 5.5 to 6.0
RAJESH RADHAKRISHNAN
VCA -DCV/WM/Cloud,VCP 5 - DCV/DT/CLOUD, ,VCP6-DCV, EMCISA,EMCSA,MCTS,MCPS,BCFA
https://ae.linkedin.com/in/rajesh-radhakrishnan-76269335
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