No metadata found

I just issued the 3.0.8 patch. Please try updating and report back.

I just upgraded to the latest Hazel (3.0.11 Build 841) and am getting a metadata error now. Detail follows:

2012-08-15 18:26:04.673 hazelworker[58890] [Error] Error during rule evaluation: Received error while trying to evaluate rule Sort by Month on file Vosk Delta
2012-08-15 18:26:04.673 hazelworker[58890] Error while matching rule Sort by Month against file /Volumes/Drobo/Pictures/Images/Second Life/Vosk Delta: Could not retrieve metadata for file: /Volumes/Drobo/Pictures/Images/Second Life/Vosk Delta
2012-08-15 18:26:04.673 hazelworker[58890] (
0 CoreFoundation 0x00007fff99bf7f56 __exceptionPreprocess + 198
1 libobjc.A.dylib 0x00007fff8fd2fd5e objc_exception_throw + 43
2 hazelworker 0x0000000100017d17 start + 92915
3 hazelworker 0x00000001000198e4 start + 100032
4 hazelworker 0x000000010001750c start + 90856
5 Foundation 0x00007fff9a8e5f39 -[NSCustomPredicateOperator performPrimitiveOperationUsingObject:andObject:] + 46
6 Foundation 0x00007fff9a8ad701 -[NSPredicateOperator performOperationUsingObject:andObject:] + 109
7 Foundation 0x00007fff9a8acfe8 -[NSComparisonPredicate evaluateWithObject:substitutionVariables:] + 290
8 Foundation 0x00007fff9a8aca9a -[NSPredicate evaluateWithObject:] + 18
9 hazelworker 0x000000010003942a start + 229894
10 hazelworker 0x0000000100039098 start + 228980
11 hazelworker 0x000000010003e696 start + 250994
12 hazelworker 0x000000010003821a start + 225270
13 hazelworker 0x0000000100022935 start + 136977
14 hazelworker 0x00000001000024e2 start + 4798
15 hazelworker 0x00000001000034ff start + 8923
16 hazelworker 0x0000000100006251 start + 20525
17 hazelworker 0x0000000100001258 start + 52

I receive this error on every image file that is evaluated.

That is something different from metadata (as indicated above, the error was being reported erroneously). I believe that's an old problem which you have to fix by opening the rule in question and saving it again (as also indicated above).