Overwrite Previous Package
From AgileApps Support Wiki
About the "Overwrite" Option
In general, the Overwrite Previous Package option means that:
- Previously installed items are deleted, if the container they are in is included in the package. (Otherwise, they are not deleted.)
- Previously installed Email templates and Quick Text items are updated, if the object is included in the package. (Otherwise, they are not updated.)
For example, suppose that a package contains an object that defines two Web Forms, and that a subscriber installed that package. Further suppose that the publisher deletes those web forms, and creates a new package containing that object. When the subscriber installs the new package, the Web Forms are deleted from the subscriber's system is the package was created with the Overwrite option. Otherwise, they remain.
Working with the "Overwrite" Option
- The Overwrite Previous Package option is enabled by your Service Provider.
- The default single sign-on setting on on-premises installation is Off.
- The default single sign-on setting on the cloud is Off. (Contact Support to make changes.)
When enabled by the service provider, a package publisher has two additional options when creating a package:
- Merge
- Previously-installed items created when an earlier version was installed are not deleted.
- They remain on the subscriber's system, even if they were deleted by the publisher.
- Overwrite
- Items in the previous package that were deleted by the packager are removed from the subscriber's system,
- with the exception of these items, which remain on the subscriber's system unless and until they are manually deleted:
- Applications (if previously added as a result of a Package Dependency
- Classes
- Global Picklists
- Global Template Variables
- Roles
- Teams
- Web Services
- Learn more: Package Items#How Package Items are Applied