February 21, 2022 By Justin Doughty
InfraWorks is a great tool in the AEC Collection, but can encounter an error that stops it being able to open models and get into the model environment.
The error will read “Unable to Open Model” with varying additional information:

We first have to remember the process InfraWorks uses to create models.
A model is started from the Model Builder, setting the location. Once processed, that project is then either saved to the cloud, or a chosen folder, either way it has to download files to the machine locally. The project is then opened. This has to be allowed to complete fully and freely, without failing or being blocked at any point along this process.
Below is a list of checks to help diagnose and resolve this issue:
Make sure all of the latest updates are applied to the version of InfraWorks being used.
Try altering the location within the Options to a local path (default shown below). Make sure whichever path is used, it is local to the PC, and that the user has permissions to edit that folder.
These also cannot be placed within the same folder, so make sure sub folders are created for each section:

Right Click the InfraWorks Icon, and “Run as administrator”:

Check the InfraWorks log files for errors. These can be found at: C:\Users\<<USERNAME>>\AppData\Roaming\Autodesk\Autodesk InfraWorks\logs
Look for certain errors:

The first part of the log, error "SSL certificate problem: unable to get local issuer certificate" would suggest to refresh and reconfirm the certificates using the Autodesk guide below:
https://help.autodesk.com/sfdcarticles/attachments/Certificate.pdf
In most new versions of InfraWorks the paths for certificates should be in:
C:\Program Files\Autodesk\InfraWorks\Git\mingw64\ssl\cert\ca-bundle.crt
The second part of the log error, shows that the files are not being downloaded. This is usually because the Model Download Manager is being blocked.
If a firewall or antivirus is being used, test either allowing InfraWorks access through it or disabling it.
An example of this that has been observed is Windows Defender blocking InfraWorks.exe, a new rule is needed to allow this.
