WinCC Flexible: 2 versions on PC simultaneously

Dear Support!

Solvable, that let WinCC Flexible Engeneering Software be two version on the PC simultaneously?

At a client yet 2005-sben carried out product development RunTime application yes. If I make a newer version up, and it is necessary to change something on that project, then to the modifications it was shopping by way of them 2005-s his licence will not be good already, if I know it well. And for my comfort client for what would have bought new llicence.

An operator panel was shopping today so I have to make the system step back, I do not can otherwise to download, because 2005 do not know the version. Today the new one OP77A-ba I cannot download a project, error message:

Hello,
It's not possible to use two version simultaneously. In your case easiest (not cheapest) is upgrade WinCC Flex 2005 to version 2008. Other possibility is todowngrade OP77A ( v 01.04.00.02...) toV01.02.00.02_01.02Look at
http://support.automation.siemens.com/WW/view/en/26437978
for more details.Hope this will helps.
With regards,Hristo Mihalev