I have Windows Insider 15048, had 15031 I believe last one.
DISM /Online /Cleanup-image /RestoreHealth is throwing me errors, even when I specify a valid source. It would say source can not be found.
And, I've found out that this is actually normal... it happens to other insiders as well?
I've discussed this issue last couple days in here UUP to ISO - Create Bootable ISO from Windows 10 Build Upgrade Files
What is the problem you are trying to fix with DISM, (and not what are the errors DISM shows)?
If just running DISM to show it has problems - you've done that already, it may be time to move on to another there are plenty more where that came from!
It's not "normal" as such, just a fact of life in beta testing situations.
Current Insider Preview Builds will only be around for ~a week, so if you have problems with any particular build that make it unusable, revert to the earlier build, and wait for the next one to come along, otherwise, if you can, work around the problems.
There is little point in trying to fix them - offer feedback, and any evidence you have to the Insider dev team, and let them do their job.
With 15031-15048, DISM is giving errors.
Had the same problem. Tried everything did a rollback on Insider and went from 15048 to 15031 with no errors now. I think it is with the 15048 release.
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