Installer error - Fout 5: Toegang gewijgerd

[Roland Hiemstra | DGMR]

Hello,

 

Some users are getting the following error when they try to run a setup:

 

“Kan een bestand in de tijdelijke map niet uitvoeren. Setup wordt afgesloten.

  Fout 5: Toegang geweigerd”

 

We were using version 6.1.2 and moved to 6.7.3.

 

The script itself has not been changed. Setups built with the older version still work for these users but the new one does not. Any idea what the issue could be?

 

Groeten,

Roland.

 

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[Gavin Lambert]

On Tuesday, June 16, 2026 at 2:47:15 AM UTC+12 Roland Hiemstra | DGMR wrote:

“Kan een bestand in de tijdelijke map niet uitvoeren. Setup wordt afgesloten.

  Fout 5: Toegang geweigerd”

We were using version 6.1.2 and moved to 6.7.3.

The script itself has not been changed. Setups built with the older version still work for these users but the new one does not. Any idea what the issue could be?

That's an Access Denied error from the TEMP directory, so it's most likely a misconfigured anti-malware app blocking access to the TEMP directory.  I don't know why that would behave differently in different versions, unless perhaps they explicitly whitelisted an older version of the engine.

[DGMR Software en IT]

I saw that in version 6.5 the following was changed:

• When available, Setup now retrieves the temporary directory path using the GetTempPath2 API, which was first introduced in Windows 11 and later backported to Windows 10 and Windows Server 2016 via monthly updates. When running under the SYSTEM account, GetTempPath2 returns a private directory (typically C:\Windows\SystemTemp), potentially enhancing security. On older versions of Windows or systems that haven't been updated, Setup falls back to the original GetTempPath API. (This change adds defense-in-depth; it does not address a known vulnerability.)

Could this be causing the issue? That the user has fewer rights in the new temp folder.

Op dinsdag 16 juni 2026 om 06:55:10 UTC+2 schreef Gavin Lambert: