@florent It is off, no snapshots.

Off:

Files:

I also disabled Change Block Tracking and deleted the ctk file.

If it helps, I'm using ESXi-6.7.0-20190802001-standard and the VM is a 10GB old CentOS.

Update: On the server side, the error looks like this:

vm.importFomEsxi
{
  "host": "192.168.1.107",
  "user": "XXXXXXX",
  "password": "* obfuscated *",
  "sslVerify": false,
  "vm": "3",
  "sr": "d5a9a2f3-3e94-b73f-f8fd-dcefdc356804",
  "network": "557d6a0f-ff4c-7692-b342-0671c0a8385b"
}
{
  "message": "Cannot read properties of undefined (reading 'current')",
  "name": "TypeError",
  "stack": "TypeError: Cannot read properties of undefined (reading 'current')
    at parseVmsd (file:///usr/local/lib/node_modules/xo-server/node_modules/@xen-orchestra/vmware-explorer/parsers/vmsd.mjs:48:30)
    at Esxi.getTransferableVmMetadata (file:///usr/local/lib/node_modules/xo-server/node_modules/@xen-orchestra/vmware-explorer/esxi.mjs:250:23)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at MigrateVm.migrationfromEsxi (file:///usr/local/lib/node_modules/xo-server/src/xo-mixins/migrate-vm.mjs:122:28)
    at Xo.importFomEsxi (file:///usr/local/lib/node_modules/xo-server/src/api/vm.mjs:1304:10)
    at Api.#callApiMethod (file:///usr/local/lib/node_modules/xo-server/src/xo-mixins/api.mjs:394:20)"
}

It looks like the presence/dependency of the VMSD file and the tool's attempt to process it has something to do with the problem.

Update: The .vmsd file is empty.