The installer for the ISM applications is called "iTwin Analytical Synchronizer" (formerly "Structural Synchronizer") and must be installed to utilize any ISM link from any application. It can be downloaded from the Software Downloads, also known as the Fulfillment Center, like any other product. A valid sign-in with the Product Download role is required.
First open the CONNECTION Center, also known as the Personal portal https://connect.bentley.com
Then click on the Software Downloads tile.
Type part or all of the word "Synchronizer" in the search field and select "iTwin Analytical Synchronizer". Note, use the American English spelling here, "z" rather than "s" in Synchronizer.
Once found, expand the All Downloads list and select the appropriate version (the top link is fine):
Click the Blue Download arrow button and save a copy of the installation file.
Starting with V8i SELECT series 5 (version 8.11.11.46) Structural Synchronizer was available in a 32 or 64 bit variety and the version installed must match the computer operating system.
Starting with the CONNECT Edition, only a 64 bit version is available.
The Software Downloads center can also be used to download the ISM Revit Plugin, or other ISM Enabled applications from Bentley Systems.
Software Downloads can only be accessed by SELECT customers and users with a Product Delivery role (see: Roles) For Non-SELECT customers, our free software, also known as iWare can be downloaded from the Bentley Resources:
Synchronizer: https://www.bentley.com/en/resources/itwin-analytical-synchronizer
Revit plugin: https://www.bentley.com/en/resources/ism-revit-plug-in
Can't Install the 32-bit Version on a 64-bit Operating System