Hi Emilia,
We are working on a new release of IGB with significant upgrades that may fix the issue. We are planning on a release sometime after the holidays in early January.
In the meantime, I would recommend removing the IGB folder located in C:\Users\<user>\AppData\Roaming\IGB on Windows, then try starting IGB again. Note that removing the IGB folder will remove any bookmarks and preferences you have created (let me know if this is an issue).
It may also be worth running IGB as an administrator. I work on Mac so I will have to confer with one of our Windows developers, but I think you would right-click on the IGB icon and select Run as Administrator.
Best,
Nowlan