There are a couple of situations that can cause the ISM commands to be grayed out and not usable.
If the Structural Synchronizer is not installed, the following things will happen.
Note, for models that are not already synchronized with a specific ISM repository, you should not be able to use the "Update Repository" or "Update From Repository" actions, even when Synchronizer is installed. Only the "Create Repository" and "New from Repository" actions are active in that case.
Install the latest Structural Synchronizer from the Software Fulfillment Center searching "Synchronizer" or the link for non-SELECT users is here.
In some cases, rebooting the computer is also required.
In STAAD.Pro the ISM buttons can be grayed out even if Structural Synchronizer is installed.
A similar problem can happen in Ram Manager version 17.00.00.93 when Synchronizer is updated to version 11.01.X. The Synchronizer can be uninstalled and version 11.00 reinstalled, or the Structural System can be updated to version 17.01 or greater. Further explanation in this forum post: ISM is showing Not Installed for Ram SS 17.00
Integrated Structural Modeling Home
RAM SS indicates ISM is not installed