What do "Update Web/Service References" and "Update to latest version" do in VS2005?

Presumably they do something different.

I still seem to have to remove and re-add references on occasion, and would like to be clear 开发者_运维技巧on what these things specifically do.

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Right, tiny breakthrough:

"Update Folder to latest version" relates to version control, not the webservice itself.

Therefore this was a quite silly question. Never-the-less, it seems I sometimes have to remove and re-add, because updating seems to not do the trick. Ho-hum.