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When I copy a file from a physical Windows 7 machine over to a Windows Server guest on a VMWare ESXi the file copy is fast for a few seconds but then drops down to a crawl of 3Mbps. Everything is on a Gbps network. How do I speed up my network connection?

I've googled a lot about it, but haven't found anyone with a solution for quite the same scenario.

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Sounds suspiciously like a write IO issue on your Windows Server VM - what storage type is the datastore that it's sitting on? How many other VM's are running on the same ESXi server and what are they doing on that particular datastore? – Helvick Sep 4 '10 at 10:00
There are 3 VMs on the same host and datastor, but they are mostly idle. Mostly the whole host is idle. The datastore is on a regular SATA drive. Its a small lab network of 2 physical computers. I tried shutting down 2 VMs and only have one running, but the problem remains. – MatteS Sep 5 '10 at 19:01
Would the server VM happen to be a domain controller? – JakeRobinson Sep 10 '10 at 6:01
You are you using thin provisioning, aka, drive space is allocated on demand? – Brennan Sep 14 '10 at 21:35

Check your vhardware network adapter, use vmxnet3 or e1000.

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