Multiple Error Reports

[Polly]

Since 03 November 2010 (when I deleted the last lot) I have 897 Error Reports listed. They seem to arrive every few minutes when I'm looking at my emails.

Some say 'APPEND' exceeded maximum size
Others say: Invalid 'addresss' field child element: country code
Others: The operation failed (code 17012)

Does this matter? Should I press the 'report' button for each one or can I continue to delete them periodically?

I should add that, as far as I can see, I am receiving and sending all expected mail, I can search for messages and move them to my folders.

Product name: Zimbra Desktop
Product version: 1.0
Build ID: 1593
Release type: R
OS Platform: Windows XP x86 5.1

Thanks,
Polly