The following errors (or similar) are seen in the SWMM output log when attempting to compute with the Explicit (SWMM) solver, though nothing appears to be wrong with any storm data or patterns.
ERROR 209: undefined object * at line 39 of [RAINGAGE] section: 1227_ VOLUME 00:06:00 1.0 TIMESERIES * IN
ERROR 203: too few items at line 907 of [TIMESERIES] section: 00:00:00 0
"One or more EPA SWMM catchments failed to compute. Check your EPA-SWMM input data and try again".
Related Defect #540746 and #623058
This may be due to a blank label(s) for your storm events. The label cannot currently be edited directly in the Storm Data manager, but you can use this workaround:
Note: if your storm data is already connected to an engineering library, skip to step 4
1) Open the Storm Data manager and click the offending storm event group on the left side2) Click the purple engineering libraries button at the top and click "export to library".3) Expand storm event groups and either select an existing storm event group library, or create a new one, select it, then click the Select button at the bottom.4) Close the storm data window and open the Engineering Libraries manager. Navigate to the event that you just exported (or if you already had your storms stored in the storm events groups library, navigate to that event), click the "collection" next to "storm events", click the ellipsis button, then change the label to something that is not blank.5) Click OK, close engineering libraries, reopen Storm Data, click the storm event group in question from the the left side, then click the engineering libraries button and choose "synchronize from library". You should now see the non-blank label and the errors should no longer occur.