If you can provide some more details, we might be able to troubleshoot your problem. What software(s) are you using? (Aggregate? Briefcase? other?) What does the date look like on the server? What does the date look like in your data export? And anything else you can provide.
The computer language settings and time zone can affect how the date is formatted, see this post for more details:
Other people have had difficulties with this:
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