I have a co-worker that installed the Salesforce Extension Pack for VS Code. There is no go to definition for apex code and it is not possible to run tests. We have tried uninstalling all extensions and re-installing the Salesforce extension but it still does not work. He had also accidentally installed the Force.com extension as well. There is no error message. It hangs when installing the Salesforce CLI Integration and also the Apex extension.
Is there some sort of extension cache that I can clear?