If you upgrade to version 4.33 of Movable type, your Monthly Archives will not work. (as of now — Jan, 20th, 2010).
Please see the below message from SixApart:
“Hi Iain,
Thanks for sharing your results; we have been able to reproduce this issue in Movable Type 4.33, and it appears that a new issue was introduced in that version (so it is not an issue with your data). Unfortunately, we don’t have a solution for this at the moment, but we will update you here if one becomes available.
If you require your Monthly Archives to be in working order, and have a backup of your database from prior to your upgrade, you may wish to revert, and then upgrade to version 4.32, which does not appear to be affected by this specific issue. Otherwise, you may want to temporarily disable the Monthly archives (and links to them) from being published, so as to avoid confusing your readers.
Regards,
~ Sarah”
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