Missing files after update install

[mo22]

Good evening,

I'm using wix 5.0.2 to create an MSI of a python pyinstaller build of a python windows service. REINSTALLMODE is currently amus.

If the app is in use during an update install MSI fails to remove the previous file:

Info 1903.Scheduling reboot operation: Deleting file ... /base_library.zip Must reboot to complete operation.

But for some reason installing the new (changed) file works:

MSI (s) (00:2C) [11:42:33:695]: Executing op: FileCopy(SourceName=9xojlb1f.zip|base_library.zip,SourceCabKey=flsJ_6JjIKoWRVxe3Rg4NLXwa1Ii_g,DestName=base_library.zip,Attributes=512,FileSize=1329520,PerTick=65536,,VerifyMedia=1,,,,,CheckCRC=0,,,InstallMode=62914560,HashOptions=0,HashPart1=-1433592414,HashPart2=1675167172,HashPart3=741024287,HashPart4=239661532,,)
MSI (s) (00:2C) [11:42:33:701]: File: C:\Program Files\MyApp\_internal\base_library.zip;	Overwrite;	Won't patch;	REINSTALLMODE specifies all files to be overwritten

At the end after restarting the file base_library.zip is deleted and ends up missing.

My theory is that stopping the service (using <ServiceControl Stop="both" Remove="uninstall" Wait="yes" />) does not really unlock end the service completely so that the file is still in use when MSI uninstalls the previous version but not any more when the new files are installed.

To me this seems to be an MSI issue - does anyone have an idea how to solve this?

Thank you very much
Moritz

[chrpai]

What are you using to host the service? Does it spawn a child process? Does telling the host to stop the service end the child process?

[mo22]

It's a service without any child processes, but it might take 2-3 seconds to terminate.

This here seems to be the same issue: https://stackoverflow.com/questions/46662471/wix-toolset-msi-upgrade-results-in-missing-files-after-reboot

As far as I understand MSI should - for all file paths that are marked to be deleted after reboot - write the new files to a temporary place and use a rename after reboot operation.

I might try to use a minor update instead but that seems to be mainly regarded as a bad idea for other reasons.