Hello,
When clicking the scroll to trigger the server to send the Gump interface, the Razor/Assistant plugin in ClassicUO encounters a packet parsing error, which causes a .NET access violation and leads to the client crashing.
Try uninstalling the current ClassicUO and switching to a different version of ClassicUO to see if this resolves the issue:
https://github.com/ClassicUO/ClassicUO/releases
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