The Error Message That Wasted Part Of My Day – or – I Am Not A Smart Man…
I’ve run into an issue that I couldn’t find documented anywhere, so I am hoping this post can help someone else in the future.
I recently stood up a new environment for a school district and it’s running ConfigMgr 1902 with ADK 1903. I prefer to have a custom boot image that is separate from the default boot images that are created with the set-up. Because I don’t want to risk breaking a boot image during an upgrade of ConfigMgr/ADK in the future. So, I open the Deployment and Imaging Tools Environment cmd prompt and run:
copype.cmd amd64 c:\bootimagex64
I take the boot.wim file from c:\bootimagex64\media\sources and place it in my site server sources folder for import. I go to Software Library -> Operating Systems -> Boot Images, select Add Boot Image, type out the UNC path to my site server sources folder and the new boot.wim file. Easy Peasy … but then I’m presented with the following error message:

The path IS valid! The Add Boot Image Wizard even completes my UNC path as I type it …
Yet it still gives me that error!
Welp – Time to troubleshoot.
First thing I checked is permissions. I verified that the site server computer account had full permissions for NTFS on that drive and within sharing for that particular share. Also, I verified that the service account had full permissions to NTFS and sharing, just in case. I even checked the permissions on the boot.wim file thinking maybe they didn’t inherit properly. None of that seemed to matter.
Next thing I checked is if the boot.wim is a valid boot image. I started up psexec in the context of system so I could run dism to verify that I could mount the boot.wim with:
psexec -i -s cmd
and then:
dism /mount-image /imagefile:”c:\bootimagex64\media\sources\boot.wim” /index:1 /mountdir:”C:\bootimagex64mount”
Then I go browse over to c:\bootimagex64mount and I can see the boot image successfully mounted so I know I can unmount it with:
dism /unmount-image /mountdir:”c:\bootimagex64mount” /discard
I was still unable to add this boot image to ConfigMgr.
So, I did what any self-respecting sysadmin would do and I went grovelling to my community for assistance. I tried the winadmins slack first, but the ideas presented didn’t get me anywhere.
[If you aren’t in the winadmins slack yet, then head on over and join us]
- I tried using an alternate boot.wim, like the ones found at <ConfigMgrInstallDirectory>\OSD\boot\x64, but was met with the same error message as before.
- Also, I really didn’t want to rollback the ADK, even just for testing purposes. I was willing to try it, as a last recourse. Since the support matrix shows it supported, but I’m stubborn.

Next I went to reddit and posted on /r/sccm to see if I could get any help there.

I was fully prepared for Jason Sandys to jump in and comment as he seems to be on the most popular Google results for this error message and he’s present on technet and reddit comments that I was looking at during my research, but I think I got an even better response…

I blame Jeffrey Snover for making me not want to click buttons, but really … I’m not a smart man. I cannot believe I never thought to browse to the damn wim file.

I came into the office today and decided to listen to /u/vsoro00 and click that browse button:
and wouldn’t you know it … it worked!

Woot! Now let’s make sure it will fully import…

I want to say a heartfelt thank you to /u/vsoro00, who I assume is Vladimir Sorokin over on the ConfigMgr team at Microsoft, for taking time to answer my post in reddit with exactly what I needed to hear. Also, I don’t understand the technical limitations they are working with or what he means about how expensive the process can be to validate everything I type in, but if this is truly an issue for others than I look forward to them removing the typing functionality altogether! I love this community!
Chris Thomas
@AutomateMyStuff
OMG, Thank you for posting this. I went through almost all of the same steps that you did verbatim. I had just started back-leveling my ADK and found this post while waiting for it to re-install. You saved me hours of more troubleshooting because of a damn textboxt/browse button bug. Thank you!