Unwanted Steam error prevented access to this

[DanDigiMan]

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This keeps happening to me, why?

*Unknown is what I meant, got it wrong

[Massacrer]

There's a few questions I need answered from you:
1. Did you update your KF?
2. Are you running non-whitelisted content?

[DanDigiMan]

My KF is up to date. And no. It's when I start the game, and not when I have joined any server.
EDIT: Problem solved. Re-installed the game!