You cannot install both packages since both contain the same component TDBTreeView.
Not 100% sure that this works, but I guess you should do this:
- Open package IBControls. Remove the units DBTreeView and probably also DBControlGrid from the file list that you see in the package editor. You'll probably also have to delete (or better: rename) the corresponding files.
- Find the registration unit(s) (the one with the green triangle in the file list of the package editor) and make sure that the components TDBTreeView and TDBControlGrid are not registered
- Add package DBControls to the requirements of the IBControls package.
- Do a clean rebuild of the IDE (Tools > Configure Build Lazarus > check "Clean All" > "Build"
Since I am not 100% sure that this works you should make backup copies of the modfied/renamed/deleted files.
Or better: contact the author of theses packages (tonyw - he is a member of this forum) and ask him to do these changes for you.