If you find a link which seems broken, try checking that it is for srgc.org.uk.
With the forum changes the links must now begin srgc.org.uk and not srgc.net !
If you still find a broken link- try changing the http to https - as in
https://www.srgc.org.uk/forum/Following forum updates in 2020 there may be security warning messages when you click on some old links for which you have substituted https as a prefix, but these are unfounded, since no security sensitive details are included or asked for in this forum.