Fix FSX installation error 1628 'Failed to complete installation' with safe steps for InstallShield, temp files, DVD media and Steam Edition.
FSX installation error 1628 means the legacy InstallShield setup stopped before it could finish. For boxed Microsoft Flight Simulator X, restart Windows, clear temporary installer files, reset the InstallShield engine, and rerun setup.exe as administrator from the DVD. FSX: Steam Edition uses Steam repair steps instead.
Does FSX error 1628 affect boxed FSX or Steam Edition?
Error 1628 normally comes from the InstallShield system used by boxed FSX, Acceleration and some add-on installers, not from Steam itself. Identify which installer displayed the message before changing anything; our comparison of boxed FSX and Steam Edition installers explains why their repair methods differ.
| Where the error appeared | What to repair |
|---|---|
| FSX or Acceleration DVD setup | The temporary setup files, InstallShield engine and installation media |
| Steam while installing FSX: Steam Edition | Steam's download cache and FSX file installation |
| A separate aircraft, scenery or utility installer | That add-on's InstallShield setup, not the main FSX installation |
For Steam Edition, open the simulator's Steam properties, use Installed Files to verify its files, and clear Steam's download cache if the download stage remains stuck. Do not rename InstallShield folders unless a separate legacy add-on installer actually produced error 1628.
How do I clear FSX error 1628?
The safest fix is to remove the interrupted setup state first, then repair InstallShield only if the error returns.
- Restart Windows. This closes hidden
setup.exe, InstallShield and Windows Installer processes left behind by a failed attempt. Do not start another installer before trying FSX again. - Check the FSX DVD. Clean it from the centre outwards and confirm that Windows can copy its files to a temporary folder without a read or CRC error. If copying fails, try another optical drive if available; cabinet-file or CRC failures are better handled as damaged-media and FSX Error 1335 problems.
- Clear the user temporary folder. Press Windows key and R, enter
%TEMP%, and delete the contents you are allowed to remove. Skip files reported as in use; do not delete the Temp folder itself. - Reset the InstallShield engine. Close all installers, open
C:\Program Files (x86)\Common Files, and rename theInstallShieldfolder toInstallShield.old. On 32-bit Windows, the equivalent folder is beneathC:\Program Files\Common Files. Renaming is reversible and safer than deleting it; if the folder is absent, skip this step. - Remove only the incomplete installation. Open Windows' installed-programs list and uninstall the partial FSX entry created by the failed setup, then restart. If error 1628 occurred while adding Acceleration, remove only the incomplete Acceleration installation rather than a working base copy of FSX. Preserve any add-ons before removing an established installation.
- Run the correct setup file. Right-click
setup.exein the root of the first FSX DVD and choose Run as administrator. Do not launch an individual MSI file buried inside the disc, and let the main installer request the next disc when required. - Try a clean Windows start. If background software keeps intercepting setup, use System Configuration to hide all Microsoft services, disable the remaining third-party services and startup items, restart, and install FSX. Restore normal startup afterwards. Check security-software quarantine records rather than downloading replacement installer files from an unverified source.
What should I do if 1628 still appears?
The final 1628 message is often only a wrapper around an earlier, more useful error. Immediately after the failure, open %TEMP%, sort by modification time, and inspect the newest setup or InstallShield log; file names vary, so look for the first failure before the closing 1628 line.
- Error 1607 or scripting-runtime failure: follow our InstallShield runtime, Windows Installer and permissions checks.
- MSXML 4 failure: repair the prerequisite using our safe MSXML 4 troubleshooting procedure for FSX, then rerun the main installer.
- Access denied: confirm that the Windows account is an administrator and that setup is not being launched from a restricted network or synchronised folder.
- Failure only in one Windows account: create a fresh local administrator account and run the DVD setup there. This bypasses damaged per-user Temp permissions and stale installer data.
Should I use compatibility mode or a registry cleaner?
Compatibility mode is not the primary fix for FSX error 1628 because it cannot repair a corrupt InstallShield engine, unreadable DVD or blocked temporary folder. Use administrator rights first; an older Windows compatibility setting should be only a final test if the clean installer still exits on a modern version of Windows.
Avoid registry cleaners, downloaded DLL replacements and manual deletion of Windows Installer records. Those measures can turn a recoverable InstallShield failure into an installation that neither completes nor uninstalls.