Are you using the latest version of SourceMod? Earlier versions won't work with the latest version of TF2.
If you are using the latest version of SourceMod, maybe post a minidump up for the bug checkers to look at what might be causing the issue
The version of SourceMod you want to be using is SourceMod version 1.2.3
Hope this helps,
President Skroob
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With a stop light, green means 'go' and yellow means 'slow down'. With a banana, however, it is quite the opposite. Yellow means 'go', green means 'whoa, slow down', and red means 'where the heck did you get that banana?'
- Mitch Hedberg