Fix FSX Error 1935 on Windows 10 or 11 by identifying the failed assembly, repairing MSXML or Visual C++, and checking Windows components.
FSX Error 1935 means Windows could not install or register an assembly required by Microsoft Flight Simulator X, usually MSXML or an x86 Visual C++ runtime. Reboot, complete Windows Update, run the boxed installer as administrator, then repair the component named in the error or Windows component store; never download individual DLL files.
What does FSX Error 1935 mean?
Error 1935 comes from Windows Installer when an assembly transaction fails. The line following the error—rather than 1935 alone—identifies the real problem. Boxed FSX commonly encounters it while installing legacy MSXML or Visual C++ components; it is not an activation error.
Record the complete assembly name and any HRESULT before cancelling setup. If the message says processorArchitecture=x86, that is normal: FSX is a 32-bit application and needs x86 components even on 64-bit Windows 10 or 11.
How do I fix FSX installation Error 1935?
- Record the complete error. Take a screenshot or write down the named assembly and HRESULT. Different Error 1935 codes need different repairs.
- Clear pending Windows servicing. Finish Windows Update, restart Windows and check that another restart is not pending. An unfinished update can prevent Windows Installer from committing a new assembly.
- Start the correct installer with administrator rights. For boxed FSX, sign in with an administrator account, right-click
setup.exeand selectRun as administrator. Do not enable an old compatibility mode as the first fix. Our clean FSX installation sequence for Windows 10 and 11 covers the edition and media-specific steps. - Remove third-party interference. Temporarily pause third-party antivirus protection or perform a clean boot that disables only non-Microsoft services and startup applications. Leave Windows Installer and Windows Modules Installer enabled, then restore the disabled software after testing setup.
- Repair the component named in the message. Use the table below rather than installing every prerequisite you can find. Unrelated runtime changes often create additional side-by-side errors.
- Repair the Windows component store. Open Command Prompt or Terminal as administrator and run these commands in order:
DISM /Online /Cleanup-Image /RestoreHealthsfc /scannowAllow each command to finish, restart Windows and try FSX setup again.
- Remove only the partial FSX installation. If the failed attempt created an FSX entry under Apps or Programs and Features, uninstall that entry and reboot before retrying. Do not manually delete shared runtime folders or anything inside
WinSxS.
Match the failed component to the repair
| Error text | Likely cause | Appropriate action |
|---|---|---|
Microsoft.MSXML2, MSXML or MSXML 4 | The boxed installer cannot install or register its legacy XML prerequisite. | Follow our FSX-specific MSXML 4 repair procedure. Do not download a loose msxml4.dll or remove MSXML 6. |
Microsoft.VC, CRT, MFC, ATL or an x86 policy assembly | An x86 Visual C++ side-by-side package is damaged or missing. | Use our x86 side-by-side runtime checks. Keep the x86 package even on 64-bit Windows, and do not uninstall every Visual C++ version. |
0x80070005 | Windows returned Access Denied. | Run setup from a local administrator account, use a clean boot and check whether third-party security software is blocking Windows Installer. |
0x80071A91 | The Windows transactional resource manager is not operating correctly. | Use the targeted fsutil reset below, restart and retry. |
| The assembly changes between attempts, or the message mentions a manifest or component store | Windows servicing files may be damaged. | Run DISM and System File Checker as shown above before changing FSX itself. |
Only when the HRESULT is 0x80071A91, open an administrator Command Prompt and run fsutil resource setautoreset true C:\, replacing C: if Windows is installed on another volume. Restart afterwards. This command is not a general fix for every Error 1935 code.
Does this apply to FSX: Steam Edition?
Error 1935 is most closely associated with boxed FSX and its prerequisite installer. For FSX: Steam Edition, verify the game files through the Steam library and rerun its first-start installation. If a prerequisite still reports Error 1935, repair the assembly named in that message rather than applying fixes intended for the boxed DVDs.
Do not install boxed FSX Service Packs or Acceleration over Steam Edition. Once boxed FSX installs successfully, use the correct boxed-FSX service-pack order for the edition you own.
What if FSX Error 1935 still appears?
If the same assembly and HRESULT persist, create a fresh local Windows administrator account and run setup there. This isolates damaged profile permissions. Changing the FSX destination from Program Files to another folder will not fix assembly registration because the failure occurs in Windows, not the selected FSX folder.
Repeated disc read failures or an installer file that cannot be copied point to damaged installation media. Copy each DVD into a separate local folder to test readability; do not merge the contents of multiple discs into one directory.
Avoid old registry-size tweaks, registry cleaners, deleting WinSxS, manually registering downloaded DLL files or uninstalling every Visual C++ package. If DISM and System File Checker both report corruption they cannot repair, Windows servicing must be repaired before FSX will install; an in-place Windows repair may then be necessary.