Paul Herber Software

You may get an error stating that the code signing certificate is not recognised.
1. Right-click the VSU3.msi file and select Properties.
2. Select the Digital Signatures tab, select the signature in the list, then click Details.
3. This will show the certificate details, click the Install Certificate button.

During the second phase of installation, i.e. when starting Visio you get an error like this:


1. Close Visio
2. Open the Registry Editor
3. Navigate to item:
\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\Security\TrustManager
4. Set items to Enabled as shown in the image below:
5. Now start Visio



This key only seems to exist on some Windows installations.
Here is an article with more explanation:
Click Once security settings