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OutSystems Installer Rejected by Windows SmartScreen


While installing the OutSystems Development Environment, or Platform Server, the Windows SmartScreen feature might show the following message:



There is also notice of a wrongly detection of malware on users with Windows Defender after downloading the OutSystems Development Environment. In that case, the path referred in the alert is: C:\Users\user\Downloads\DevelopmentEnvironment-9.1.x.xx.exe


This applies to Windows 8, Windows 8.1, Windows 10 or Windows Server 2012.


This is a known issue, where OutSystems installer files are wrongly classified as malware, and this is already being followed with Microsoft.

Update Aug 10, 1026: Microsoft has responded to OutSystems confirming that the wrongful classification as malware has been reverted. Relevant excerpt from Microsoft's statement to OutSystems below:

We can confirm that there are currently no active ratings for this file. Users should not experience any malware detections. Reputation has been restored to the certificate used to sign this file, so warnings should not appear on download or execution for this file or other files signed with this certificate.

Client caching could cause warnings to be seen for a few hours.  However, new visitors to your sites should not experience any warnings at this time. Clearing the browser cache will also cause a refresh of the page.



If the software package was downloaded from, these alert messages can be safely ignored and the installations completed.