What isolation level are you using for your transaction processing?  Several of the isolation levels will lock the table on the first update, so you would be able to retrieve a record, but then after updating it, you wouldn't be able to query again until you committed or rolled back the transaction.

I have a problem with locking/timeouts within one of my business objects.

I have a routine in my ControlBO that gets the last transaction reference number, increments the value by one, saves it and returns the value.

My posting routine makes a call for each record to my ControlBO.GetNextTransNumber to retrieve the next transaction number. (By the way, I am using transaction processing).

Everything works perfectly if I only have one record to process, however if I have more than one record to process, I get a timeout on the FillDataTable command on the second record trying to get the next transaction number.

Any ideas on why this is happening?