I have a situation in which my uninstall is failing because a file to be removed cannot be accessed. I understand why this is the case and I know that the file will be accessible when the RemoveFiles action occurs.
The questions are
1. Can I tell InstallValidate to ignore this file? 2. If the answer is no, can I tell the installer to not remove this file in the RemoveFiles action (and therefore skip validation) and remove it myself using a custom action?
If I understand your situation correctly, you have a file that you install that is not accessible during costing, so your uninstall rolls back?
Have you tried marking the file as permanent in the install (so Installer doesn't try to mark it for uninstall), then removing it either in RemoveFiles (with a dummy component, if necessary) or a custom action?
(And are you sure you can't somehow "correct" the situation making it unaccessible in the first place?)
