We had a situation where a 2008 R2 server has very slow download\transfer speeds across a WAN\ Internet on a new server using 2008 R2, if we change the OS its all good and if we do another server its all good.
- We investigated the network looking for issues with switch and routers
- Disabled all advanced network protocols
- netsh int tcp show global to view
- netsh int tcp set global <parameter>=disabled
- disabled all from NIC properties –> configure
- various other bang your head on the wall
- Lots o research
- Found some info indicating that on the Win 7\R2 Kernel if you have more memory than the OS supports it can cause a related issue.
Remove all memory over what the OS supports: i.e 2008 R2 standard = 32gb/
It sounds totally weird but its true.