Why does my installer always prompt for reboot

Question

I only want to reboot when uninstalling. This is a fragment from my WiX file:

<InstallExecuteSequence>
  ...
  <Custom Action="CleanRegistry" Sequence="7100">REMOVE~="ALL" AND NOT UPGRADINGPRODUCTCODE</Custom>
  <ScheduleReboot Sequence="7200">REMOVE~="ALL" AND NOT UPGRADINGPRODUCTCODE</ScheduleReboot>
</InstallExecuteSequence>

Running the generated MSI produces the following log:

MSI (s) (48:7C) [10:19:29:951]: Skipping action: CleanRegistry (condition is false)
MSI (s) (48:7C) [10:19:29:951]: Doing action: ScheduleReboot

How is it possible that the same condition evaluates to False then True? Does ScheduleReboot ever ignore its condition?

Edit: I am also trying to use the condition REBOOT~="Force" to conditionally execute a command when a reboot has been requested by my customaction. This condition is never evaluating to true and my command is not being run. The property is being set by a call to MsiSetProperty from a custom action. Either this custom action is not working or I have made a mistake in my condition! Any suggestions?

Answer 1

Some action might be setting the REBOOT property. You should be able to see that in the log. The most common reason is probably files in use.

Answer 2

I don't know why the original code was failing but I have ended up settling on the following which only does a reboot on upgrade or uninstall.

<ScheduleReboot Sequence="7200">REMOVE~="ALL"</ScheduleReboot>