When you install Adobe InDesign CS3, you receive the error message, "Critical Errors were found in Setup."
Solution 2: Run the Adobe CS5 Cleaner Tool before you install InDesign CS3.
The CS5 Cleaner Tool helps resolve installation problems for C5, CS4, and CS3 products. For information on downloading and running it, see Resolve installation problems with CS5 Cleaner Tool (cpsid_82947). Follow the onscreen instructions to remove InDesign CS3.
If the prerelease version of InDesign CS3 was not fully removed or is still installed, the retail version cannot install. Running the Adobe CS3Clean script removes the previous version and enables installation of the retail version.