Hi there,
There are two settings called Control which extensions cannot be installed, and Allow specific extensions to be installed in the Local Group Policy Editor. If these settings are set to enabled or wrongly set up, you cannot install extensions from the official repository.
There are two Registry keys you need to take a look at – ExtensionInstallAllowlist and ExtensionInstallBlocklist. The former defines the Allow specific extensions to be installed setting, whereas the latter represents Control, which cannot be installed.
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