Thanks to all for their suggestions and posts (at least I know I'm not alone!). Here's an update. After submitting the MOSDAL reports (26 June) as requested by MS Support, it all went quiet. On 11th July, I was contacted by a different support engineer
and we started again. I was sent some logging s/w and sent in some logfiles for SDPTrace, msosync, office and groove
I then had to change PCs! So went through the whole install procedure for everything on a brand new Dell running same environment (Win7 Pro 64 bit, Office 2010 desktop, Office 365 cloud) so it was a completely squeaky clean factory fresh fully updated and fresh
download of Office 2010 as at 15th July.
It worked fine. Lync Basic installed, SkyDrive Pro installed, all working as you'd expect. No idea why.
For a week..... On the 22nd July at around 13.40, the Microsoft Office Download Cache reported the same error. I had not installled anything that day. Instead of doing any fixes, I just reported it as part of the case so MS could see exactly what was happening.
The same support engineer contacted me and we started to look again on 25th July. I sent in more logfiles.
On the 29th July, the engineer sent me a "copy of our scope agreement for your issue"
And I am awaiting further response.
In summary, having replicated the issue on a brand new PC with fresh install, we still have two PCs where the MODC error prevents SkyDrive Pro working, and two PCs where we have not installed Lync Basic 2013 where Sky DrivePro and MODC/MDUC work fine without
error.
I'll post updates as and when.