riro

And, if you have drivers in the bootimages you should export them first so you have some clue of what to import in the new bootimages... http://www.snowland.se/2015/09/03/export-import-boot-image-drivers-needed-before-adk-upgrade/

I can confirm that this issue exists and the workaround works perfect. Currently migrating from CM12 to 1511 and we did some cleanup of categories before starting the migration... Did a somewhat ugly hack to find all ID's from the logfile... $instanceIDs = @() $logFilePath = "C:\Program Files\Microsoft Configuration Manager\Logs\migmctrl.log" Get-Content -Path $logFilePath | ForEach-Object { $s = $_ if ($s -like "*Couldn't find the specified instance SMS_CategoryInstance.CategoryInstance_UniqueID='DriverCategories:*") { $s = $s.Trim() + "'~~" $s = $s.Substring($s.IndexOf("CategoryInstance_UniqueID='DriverCategories:") + 45) $s = $s.Substring(0, $s.IndexOf("'")) $instanceIDs += $s } } $instanceIDs | Sort-Object -Unique