I have done a new (not upgrade) install of Windows 10, installed GnuCash 2.6.7 and run 
 Install Online Price Retrieval for GnuCash
to install Strawberry perl + Finance::Quote.
This failed when C:\Program Files (x86)\gnucash\bin\install-fq-mods.cmd ran 
 echo (yahoo "AMZN") | perl -w gnc-fq-help
saying something like Date::Manip was missing (sorry, I did not record exact error).

I tried to 'Get Quotes' in GnuCash and got error :
 *There was an unknown error while retrieving the price quotes*

In a command window:
 cd \Program Files (x86)\gnucash\bin
 echo (yahoo "CSCO" "JDSU" "^IXIC") | perl gnc-fq-helper
showed Date::Manip was missing.

In a command window, ran:
 cpan install Date::Manip
and Get Quotes now works.

I see src/quotes/gnc-fq-update.in was modified 10/2/2015 for 2.6.7 to remove install of Date::Manip (+others). Date::Manip (only) needs to be put back.
Finance::Quote does not require Date::Manip but GnuCash uses gnc-fq-helper to interface to Finance::Quote, and gnc-fq-helper DOES need Date::Manip.

BTW GnuCash seems to work fine in Windows 10 in all my testing so far, apart from this problem.