youre not the only one.
Ive learned from experience its WAY too soon to transfer clients into the new software, way too many bugs to be worked out. I wait until January.
I have the same error message. Almost all files transferred fine except for about 10 files. Called tech support - told to check that my computer is updated (it was) and told to google the error message for instructions. I did that also and nothing worked. I realize it is "Beta" but I use the checklists from Proseries to go with my year end mailing. Hopefully when I call next week they will have a better answer.
I'm sorry you ran ran into this Transfer (146) issue. It will be fixed ASAP. In the meantime, there's a workaround you might want to use if you have one or two of these.
1. Create a New Client
2. Choose File-> Transfer and select "Complete Transfer". Browse for the file you'd like to transfer.
If you have a lot you would probably want to wait a week or so until a fix goes out. Again, I'm sorry you ran into this issue and appreciate your patience.