On 13.08.2020 20:25, Mike O'Brien via Cygwin wrote:
> My first and only post —
> 
> I would like to upgrade/update/switch from Cygwin32 to Cygwin64 (on Win 
> 7x64, sp1) and I'm not so sure what all the likely pitfalls may be. 
> Would appreciate any pertinent advice, informational links, etc. that 
> experienced users may wish to share. I've searched around and pieced 
> together a few insights, but I would be remiss not to ask here...
> 
> TIA.
> 
> Mike O'B.
> 

duplicate installation with the attached script

   ./cyg-reinstall.sh -A
   sed -e "s/setup-x86/setup-x86_64/" cyg-reinstall-x86.bat > 
cyg-reinstall-x86_64.bat

run the "cyg-reinstall-x86_64.bat" script in the same directory of
"setup-x86_64.exe"

after you can use your 32bit to copy the /home/<your_user>
and all the content of "/etc" that you have customized.

Regards
Marco