Hi TROY SMITH,
Build 26300.8935 belongs to the Experimental channel, so first check Settings > Windows Update > Windows Insider Program and confirm that the PC is still enrolled in the corresponding channel. If Windows Insider settings show Release Preview instead, that mismatch may prevent the device from being offered a compatible upgrade.
Since the installation has already rolled back many times, I would avoid repeatedly running the same update. Disconnect nonessential USB devices, temporarily remove any third-party antivirus or system-tuning software, restart the PC, and try Windows Update once more.
If it rolls back again, please open Settings > Windows Update > Update history and share the exact update name and error code shown there. The error code is important because a rollback can be caused by several different driver or compatibility issues, and the appropriate fix depends on the specific code.
Please back up important files before making further upgrade or recovery attempts. A clean installation should be considered only if the PC cannot receive a compatible Insider build after the underlying rollback error has been identified. Thank you so much for your understanding.
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