The folks at Alpha 5 have a useful spreadsheet format comparison of Microsoft Access, the various Filemaker versions, and Alpha 5. Useful for the comparisons and also just to see the specs and limits for your favorite database. Check it out here: http://www.comparealphafive.com/

And here is their blog site for more details: http://blog.alphasoftware.com/search/label/Comparison%20grid

From time to time, Microsoft Access databases may start to report errors. Forms won't open, Access will warn that the file is not a recognizable database. ("Unrecognized database format mymissioncriticaldatabase.mdb")

These and other scary messages can take the breath away, and depending on the severity, ruin an hour, a day or a week. Here are steps we take in escalating order: