If that's what it states in the documentation (TRIM7.33_Spec.pdf), then that's correct. Server 2003 and Office 2003 are particularly old now and hence the latest TRIM releases aren't tested or supported on those platforms.
Also be aware that users will lose their 6.2 global settings, interface customisations, and probably favourites etc. when upgrading from 6.2 to 7.x. Plenty of forum posts on this subject too. Plan to roll out a new set of globals as part of the 7.2 upgrade project.
Also 7.x clients aren't officially backward-compatible with 6.2 workgroup servers. Keep this in mind when planning the upgrade, as the usual staged rollout process where you upgrade clients first, then servers later (as you might do for a 6.x or 7.x service pack upgrade) isn't a supported option (it may work but isn't tested, hence isn't supported by HP).
Note: Any posts I make on this forum are my own personal opinion and (unless explicitly stated) do not constitute a formal commitment on behalf of HPE.
(Please state the version of CM you're using in all posts.
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