I found that a combination of these answers solved the problem. I spent a lot of time verifying whether Skip Install was set to Yes on all linked projects and it turned out that was only part of the issue for me. If you're experiencing this issue with Archive, here are the steps to take:
- Find the archive in the Organizer, right-click and select Show in Finder.
- Right-click the .xcarchive file in Finder and select Show Package Contents.
- Find the Products folder and see what's in it. There should only be an Applications folder in the Products folder, and the Applications folder should contain only one iPhone app (YourProject.app).
If, in step 3, you find a static library (<some-library>.a) either directly under Products or in a subfolder, go to Xcode and select the project that produced the static library (you should be able to tell which project it is based on the name of the static library). Go to the Build Settings and select the target, then set "Skip Install" to "Yes".
If, in step 3, you find header files (<some-header>.h) either directly under Products or in a subfolder, go to Xcode and select the project that contains those headers. You should be able to find the project based on the prefix used in the header file names. In that project, go to the Build Phases, and in the Copy Headers section, move all headers from the Public and Private sections to the Project section.
Thanks to this answer and this answer and this answer for helping me to resolve this.