I have set up a couple of alert summary reports (monthly and ytd) for 2 different monitoring groups that are supposed to go out the first of each month, but didn't run.   The logs show the error:

1 Aug 2009 07:00:07:393 java.io.FileNotFoundException: D:\Program Files\AdventNet\ME\AppManager8\Reports\MAD1\SOX Monthly Alert Summary_2009-August-1_7_0\SOX_LastMonth_EventReport.pdf (The system cannot find the path specified)

I tried changing it to a daily to test it and same thing.  I recreated it and it went out fine the first test, but not the second time - same error.   There is no issue with running the reports themselves manually.