Re: [development] Forum error: Invalid argument supplied for foreach() in node.module on line 521

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* warning: Invalid argument supplied for foreach() in /modules/node/node.module on line 521.

This is almost always a case of node_load being called without a node id.

Right, more precisely, the nid is coming from a db query which comes back empty handed thus the fetch will be FALSE and then node_load fails with this error.