thanks Stefan for your help,

How can I know which version of Step 7 v5.x by looking at the .ver files?
Since the HMIs are created with TIA16 and the logics with S7 5x, is it better to purchase a combo license or licenses separately?

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Split from Tia 16, there is no Main block .

Hi soodeh.f,

you should be able to see the version in the file "Global\PROJECTVERSION.umf" within the project. But unlike the TIA Portal, the versions of the classic STEP 7 are compatible. So I would use the newest version of STEP 7 as long the PC is compatible.

I don't know the exact prices, but buying a combo license will be cheaper than buying STEP 7 Professional V17 and STEP 7 Professional 2021. Unfortunately, there is no possibility to upgrade an TIA license to a combo license, only "classic" licenses (in this case STEP 7 Professional 2021) can be upgraded to combo licenses.

Kind regards
Stefan