Quote:
I found the following but I can't seem to get it to work.

https://forums.mirc.com/ubbthreads.php?ubb=showflat&Number=183920&page=0#Post183928

During the rejoin it shows "AUTOJOIN Unknown command" in the status window. Is the script faulty or something else?

Quote:
No BNC, just standard Mirc and without any scripts running either.

Hum, the "autojoin" command was introduced in mIRC v6.17, so I think you just need to update your mIRC... Also make sure to put the script in a separate "remote scripts" file.
Here's a modified version of the script that won't evaluate channel names.
Code:
on *:disconnect: { set -e %disconnectedcids $addtok(%disconnectedcids,$cid,32) }
on *:connect:{
  if ($istok(%disconnectedcids,$cid,32)) {
    autojoin -s
    var %i = 1
    while $chan(%i) { $+(.timer,delayjoin,$cid,$chr(1),$v1) 1 $calc((%i -1) *10) join $!gettok($ctimer,2,1) | inc %i }
  }
}

This should make you rejoin each channel with a delay of 10s.