The @ symbol shouldn't matter, I did a quick test of parse_url in PHP and it appeared to correctly identify that it was a username, which is good. Other stranger characters might not play as nicely.

What I think is happening is that there is some form of weird mismatch going on if it isn't putting it in the right place. Trying to think of a way of easily detecting that though (or detecting at all).

Has this got something to do with the version of J! that is currently being updated from?

I can update from J! 1.5.12 & .13 to .14 but am having all these same issues when updating from 1.5.3.

All these sites are on the same server and the settings for FTP and update manager are identical for the three sites.

There appears to be some weirdness with some releases the further back you get but it doesn't appear to be consistent for each site.

What sort of error does it give you?

Same as cpmdoc and kupkake832

Just for the exercise I upgraded to 1.5.10 (found the file locally) and then ran the updater and all went as it should

Hope that's helpful Sam

Will have to do some experiments with low J! releases and going from them. Good to hear its fine once you're up to date.

One of "THE BEST" bits of coding

Should be a part of the base install