I have not been able to reproduce this issue. These are the steps I've followed using Putty.
1 . In Session -> Host Name I added the aws ip
2. In Connection -> Data -> Auto Login Username I have added bitnami
2. In SSH -> Auth I've added the aws pkk file.
3. In SSH -> Tunnels - Destination I've added localhost:80
4. In SSH -> Tunnels - Source Port I've added 8888
Can you confirm you've followed the same steps?
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