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Chien-Pin Wang wrote Zope with type TransactionError. The coresponding error value says: Traceback (innermost last): File /usr/local/Zope-2.1.6-src/lib/python/ZPublisher/Publish.py, line 169, in publish File /usr/local/Zope-2.1.6-src/lib/python/ZODB/Transaction.py, line 209, in commit TransactionError: A serious error, which was probably a system error, occurred in a previous database transaction. This application may be in an invalid state and must be restarted before database updates can be allowed.

This means that a previous transaction failed. You need the traceback from the request that failed. Other than that, you can't do much but restart. Anthony