That depends on error message. These messages are well-descriptive. There may be several variants:

• Incorrect login or password. The message will be as follows: “Incorrect username or password”. The solution is to enter the correct authentication data.
• User is blocked. There will be the corresponding message. The solution is to send an e-mail to support@mypodcast.com
• Server internal error.

In any case you can record your episode in another application and try to send the episode via web-interface.