Convert VMware OVA ver. esx 4.0 to VMware OVA ver. 5 or 6

What is more important is the hardware version of the VM that was exported. There is no different versions of OVA. Can you check the Hardware version of the VM and see if it will be compatible with 5.0? It mostly will be. Then deploy the OVA and upgrade the HW version if the VM to make it complaint with 5.0 and also to use it with 6. That's the only way to convert the version I can think of.

what Virtual Data Center ?

I have VMware esx 4.0, is running in our server room, we need to migrate to VMware 6.0 but this is running on the cloud ( named IPlan  Virtual Data Center), and only accepts uploads of Virtual machine
of version 5 or 6 exported in OVA format.

does this fail with an error message when you try to import ?

do you not have access directly to the host server to Import ?

The importation fails with error ( no error id, no much info about the error ),

and this is done using vmware cloud utils.

I haven't access to the host,  is a virtual hosting service similar to Amazon, but with more features,

and cheaper. The problem is they are running vmware esx 6 and I am running esx 4, and the only

method to migrate is importing a OVA template.

Can you use VMware Converter ?

otherwise, you will need a temp, ESXi 6.0 server

ESXi 4.0 --> Export, Import --> ESXi 6.0 ---> Export, Import ---> Cloud

Sounds, good. But temp ESXi 6.0 server, means we must to buy one, or there are a trial or temporary license.

Regarding VMware Converter, I installed one, but I missing something or this tool cann't handle OVA files, and needs other ESXi 5 o 6 server to convert.

To add onto what Hancock I have to double check but you could possible down and install VMware Player which is free and import the OVA then which will create the VM then export it again with the update hardware version? If you do not want to install the free trial of ESXi 6 a trail version of VMware workstation is also an option