Some IRC networks, most notoriously Freenode, have NickServ services that are slow to respond to `/msg NickServ identify <password>` commands. If NickServ is too slow, then XChat will try to autojoin channels requiring registered nicks before your nick is authenticated. For example:
There's no way that the editor has found to get XChat to wait on NickServ, but there is an XChat setting to control how quickly it autojoins channels. Type this into an XChat window, replacing <seconds> with the delay you want, and XChat will wait that many seconds between connecting to the server and autojoining your favorite channels on it:
- /set irc_join_delay <seconds>
The default is 2, for two seconds. Setting it to 3 or 5 won't add too noticeable a delay, but setting it as high as 10 may be necessary if XChat is still autojoining too quickly for a slow NickServ.