Insider Preview update issues for 19035 or any other version.

[Snuffy]

Found that many people having issues with upgrade to 19035.1 - with some very strange Errors. so I have found a 99% fix for. You can use as a bat file or do manually. couple of things to do first.
1. locate you last iso you use to install Windows with, mount and check the drive letter you will need to change in the script.
2. open the iso and see if you have install.wim or install.esd
3. depends if esd or wim... change as needed
DISM /Online /Cleanup-Image /RestoreHealth /Source:ESD:X:\Sources\Install.esd:1 /LimitAccess
or
DISM /Online /Cleanup-Image /RestoreHealth /source:WIM:X:\sources\Install.wim:1 /LimitAccess

4. I you use ADK or VAMT3.1 (Volume Activation ManagementTool) open control panel and uninstall.
5. copy each line and run one at a time or make into a bat.
Dism /Online /Cleanup-Image /ScanHealth

Dism /Online /Cleanup-Image /CheckHealth

Dism /Online /Cleanup-Image /RestoreHealth

sfc /scannow

net stop wuauserv

net stop cryptSvc

net stop bits

net stop msiserver

ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
del /s /q c:\windows\SoftwareDistribution.old

net start wuauserv

net start cryptSvc

net start bits

net start msiserver

Next when all is complete - do a restart and then check WUA and retry the DL and Install.