• It's been years since I've had to deal with ODBC, but I think I can point you in the right direction.

    MS Access is holding an ODBC connection that it believes is open. When you attempt to use that connection (call a function), it discovers the connection is no longer open and throws you the S1T00 error.

    This issue will happen when a single connection is held open indefinitely. ASFAIK, you can't prevent it from happening.

    I remember writing a C++ program that held open a single ODBC connection. This was one of the codes I checked for on error. When this one came up, I disposed the connection, opened a new one and retried the statement. I don't know if you have this kind of code capability in MS Access.

    Later on, I stopped using a single connection. Whenever possible, I use connection pooling. You should be able to turn on connection pooling in ODBC. At that point, ODBC should handle getting you a usable open connection from the pool.