I have a similar issue. I am trying to migrate data from MSSQL to MySQL, and I feel that I have checked everything. Both MSSQL and MySQL are running locally. I am the only user on this desktop. I have tried and tested many times to see that full database permissions are granted on both MSSQL and MySQL sides. I have tried through the MySQL Workbench migration wizard and through command line. It seems that there could be something wrong with how the migration throws this error: "ERROR: Determine number of rows to copy" I am grateful for everyone who works on MySQL - but there has to be some kind of error in wbcopytables executable - or at least how it throws errors. It may be a bit of data, but it really isn't that big. I would think that the people who work on MySQL would want the transition from MSSQL to MySQL to be smoother. At this point I feel that I have tried every option in both the UI from MySQL Workbench, and also from creating a .cmd file.