Extensions were not installed properly is this normal?

Hi, I recently did an erase and install of Snow Leopard. After the install I used Migration assistant to restore all my files. Before it completed I got about 7 messages that extensions were not installed properly and need to be reinstalled. One of them had something to do with my Canon Printer and the other was for my Elgato TV Tuner. I'm not sure what the other extensions were. Is it normal for some extensions to not restore correctly after using Migration assistant?

 

Thanks. So what should I do?

I should just reinstall the applications? I don't know what the other extensions were. is there a log that can tell me?

 

Hi, I reinstalled the printer but the message popped up again. I trashed the extensions and then reinstalled the printer and so far the message hasn't popped up. Is it ok to trash the extensions?