3 replies to this topic

[tim]

I am creating an upgrade that adds and removes components and features and that also updates existing files.  I understand what I have to do in order to add or remove new features and components, but I'm a little confused on updating an existing component.  Here's an example of what I have and what I would like to do:

The original package contains about 185 files.  The main files I need to update are 1) the main exe file, and 2) many crystal report files.

I would like to create a major upgrade (from version 2 to 3) that will migrate the existing feature state while removing unused files.  It should not be possible for both versions to exist on the system.  I would like to update the changed files without having to change the file name or location, if possible.

From what I understand from Microsoft's documentation, if I change the component code, the file name or location must be different.  If I don't change the component code, it must be backwards compatible with any previous version on the system.  

I'm confused; do I still need to follow this rule if I uninstall a previous version first?  If I try to update the file using the same name, location and component code, will it work properly?

I would greatly appreciate any feedback on this subject.

Thanks,
Tim

[Martin Aigner]

The change of component code depends on several conditions:
If the file is a shared file you must not change the component code (if you do this, the component counter starts at 0 and this file will be deleted, if your application will be uninstalled).
If the new version is not backward compatible, you have to change the component code and the location of this file. In this case you have to use this file side-by-side (install this file in the same location as the calling exe-file and add a file named like the calling-exe but with the extension .LOCAL to this location. Sample: if the calling application is named Application.exe you have to add a file named Application.exe.LOCAL to the same folder).

If the files are not shared files, you don't have to change the component code. In this case, the files will be updated without problems.

[tim]

Thanks for your reply.

The file is not shared, so I don't have to worry about that condition.  The file is not backwards compatible, but I don't really care since both versions will not exist on the system at the same time (I'm uninstalling the old version first).  Therefore, I should be able to update the file using the same component ID wihout any problems.  Is this correct?

Thanks,
Tim

[Martin Aigner]

Yes, it is.