Windows Embedded Standard 7 CTP/RC and RTM answer files compatibility issue

This morning, while building a Windows Embedded Standard 7 image for a project, my colleague and I encountered an unexpected sneaky problem. In the office we have various development machines equipped with different versions of Windows Embedded Studio 7 (which we’ve installed as soon as Microsoft released it for testing during the last months – CTP, RC and RTM). We started to migrate all machines to RTM version, so now we have a number of projects made with CTP and RC (when the product was still named Windows Embedded Standard 2011) and others with RTM. We had never tried to use an answer file from a pre-release version with the final RTM, until today. And unfortunately there are no good news: it took us some hours to figure out a strange problem about DISM during image deployment (IBW log files just reported an error installing an INF file, no other info).

It was strange because we created two similar answer files (they just differed on EWF and FBWF protection), one with ICE RTM and the other with ICE CTP, which we deployed on the same target device without problems. Then we had to edit both answer files and we used ICE RTM: with the file created with ICE CTP, the tool alerted us of a problem with the Distribution Share folder (that was obvious, because the product changed its name and installation folder from \Program Files\Windows Embedded Standard 2011 to \Program Files\Windows Embedded Standard 7), but after using the correct DS, no more validation errors occurred. So we thought that everything was fine and ready for a new deployment. But that was not true! While deploying the CTP-RTM updated answer file, the problem with DISM occurred; while using the RTM-only answer file, everything worked fine. We tried to figure out the problem by modifying the edited settings, thinking that we used some bad values, but nothing changed. At the end, we re-created from scratch the CTP answer file using ICE RTM, and magically everything worked.

Thus, it seems that some compatibility issues exist between Windows Embedded Standard 7 CTP/RC and RTM answer files. To avoid any problems with your pre-release answer files (maybe you received a pre-release promotional evaluation kit), we suggest you to re-create your projects using the RTM version.