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Customization spec failing after OSOT

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We are deploying a persistent pool for some of our users which require customized software and more RAM.

We have updated our golden image and re-run the new OSOT (VMware OS Optimization Tool) Template+LGPO utility to maximize performance.

We previously had a vcenter customization spec that worked great, for making persistent machines. When we run it against the images now, we get an error "Error opening file C:\WINDOWS\Panther\unattend.xmlThe system cannot find the path specified" visible in the logs and I see no unattend.xml in the location.

If I clone a copy of the image before the OSOT was run, the customization spec works like a charm - but, a lot of work has gone in to the image after the OSOT was run so we'd rather not repeat all that, and miss out on the performance benefits the OSOT template offers.

Any thoughts/things to look at/advice?

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Managed to fix this by backing out all my changes to my pre-OSOT snapshot and going through, making some conservative best-guesses on services not to disable, features not to turn off, etc. in the template.

Unfortunately due to time constraints I couldn't track this down to an individual setting or settings (needed to complete the project ASAP) but something in both the new Windows 10-2019 AND the older Win10 1809-2004/Server 2016-2019 templates breaks the vcenter/vmware tool's ability to place the unattend.xml where it needs to on the VMs.

Be cautious and manually review what settings you enable in the OSOT - even from VMware's recommended pre-checked options. Though, that's just generally good advice as the tool is kind of a shotgun - huge performance gains but some potential collateral damage.

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Contributor
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Managed to fix this by backing out all my changes to my pre-OSOT snapshot and going through, making some conservative best-guesses on services not to disable, features not to turn off, etc. in the template.

Unfortunately due to time constraints I couldn't track this down to an individual setting or settings (needed to complete the project ASAP) but something in both the new Windows 10-2019 AND the older Win10 1809-2004/Server 2016-2019 templates breaks the vcenter/vmware tool's ability to place the unattend.xml where it needs to on the VMs.

Be cautious and manually review what settings you enable in the OSOT - even from VMware's recommended pre-checked options. Though, that's just generally good advice as the tool is kind of a shotgun - huge performance gains but some potential collateral damage.

View solution in original post

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Which Windows version did you use?

For visibility it would be better to use the comments or bugs section on the flings website.

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