Migration MSAccess->MySQL in Workbench problems.

[Lars MOngs]

I don't understand how this works:

In Workbench 6.3.7 in Migration Wizard the Source Selection is set as:
1. I am choosing my source MSAcessDB in 'Source Selection' by selecting 'Microsoft Access' from the list of supported systems.
2. Connection Method='ODBC Data Source'.
Parameters:
3. DSN= 'MS Access Database (Microsoft Access Driver(*.mdb, *.accdb)'.
(I have set User DSN: arxwebtab1.mdb - 'MS Access Database (Microsoft Access Driver(*.mdb, *.accdb)' in ODBC Data Source Administrator (32-bit)).
4. Default Character Set='cp1252'.

The thing is that I could have MULTIPLE databases (*.mdb) being connected to this Microsoft Access ODBC Driver.
How does the system know which .mdb-file I am referring to by just setting the DSN to 'MS Access Database (Microsoft Access Driver(*.mdb, *.accdb)'??
How does it know I am now aiming at migration from 'arxwebtab1.mdb' and no other AccessDB??

BTW, when I put in these values and do 'Test Connection' I get 'Test Source DBMS Connection, Operation cancelled'.
When trying to go on into 'Fetch Schemas List' I get this:
ERROR: Exception in task 'Connect to source DBMS': SystemError('Error("(\'HY000\', \'The driver did not supply an error!\')"): error calling Python module function DbMsAccessRE.connect',)

SO I don't understand and I get an error..
What can I do?
Can you help me out??

TIA