Reports 301 and 302 when links seem valid

301: Means the links is permanently moved. You need to update this link. It works today, but you are redirected to a new URL. This may change as the URL may only provide this permanent update only for 6 months, but no longer. After the server owner removed the update rule your link may becomes a 404.

302: Means a temp change. You need to check out what's wrong/changed, but it doesn't mean for sure an upcoming defect. It could also be a session URL redirection. Then you can ignore it - otherwise often servers send 302 where they need to send a 301...

Hope this helps. Otherwise search the net... this is very technical stuff that may need verifying eyes... :-) aside 403 is permission denied.

Without the links I cannot verify.

If you click on a link named http://example.com/foo, but a second later you are on http://example.com/bar your browser should have got a 301 or 302... There is no redirect page shown to you, but the URL in your browser changes very quickly... so - yes the users lands on the correct page, but you as site owner of your site linking to an external site may end up with broken links in future and should better update the links asap.

It really shouldn't report it like a broken link then. Would it be possible to provide a warning like: "This link will change in the future?"

Just spent a few hours and mails back and forth with the host trying to find out why I was getting a broken link report. Only to realize it's a false positive.
This is the message I get:

Link check of http://www.fanc.fgov.be failed 3 times (status code: 301).

This is what the host sent me:

root@europe:~# wget http://www.fanc.fgov.be 
--2011-03-16 10:05:49--  http://www.fanc.fgov.be/ 
Resolving www.fanc.fgov.be... 194.78.247.24 
Connecting to www.fanc.fgov.be|194.78.247.24|:80... connected. 
HTTP request sent, awaiting response... 301 Moved Permanently 
Location: /page/homepage-federaal-agentschap-voor-nucleaire-controle-fanc/1.aspx [following] 
--2011-03-16 10:05:50--  http://www.fanc.fgov.be/page/homepage-federaal-agentschap-voor-nucleaire-controle-fanc/1.aspx 
Reusing existing connection to www.fanc.fgov.be:80. 
HTTP request sent, awaiting response... 200 OK 
Length: 35637 (35K) [text/html] 
Saving to: `index.html' 

100%[======================================>] 35,637      --.-K/s   in 0.02s 

2011-03-16 10:05:51 (1.90 MB/s) - `index.html' saved [35637/35637] 

I see on the project page "Updates permanently moved (301) links after specified link check fail count"
Where can I find more info on this? I dont really understand.

Uh my goodness... this is a nobrainer. http://www.fanc.fgov.be/ should only send you a 302. An 301 is a permanent change. In this special front page situation a 301 is always wrong. This is a bug in their site's redirection rules...

If they permanently move a URL content from http://www.fanc.fgov.be/page/this-is-my-old-link.aspx to http://www.fanc.fgov.be/page/homepage-federaal-agentschap-voor-nucleaire-controle-fanc/1.aspx - than and ONLY than a 301 is correct.

An 301 need to be reported as a fail in linkchecker - as it must tell You - you need to update your outdated http://www.fanc.fgov.be/page/this-is-my-old-link.aspx link to http://www.fanc.fgov.be/page/homepage-federaal-agentschap-voor-nucleaire-controle-fanc/1.aspx ASAP or it may break. If you have not configured the auto-update feature in linkchecker settings than you must do the link update manually. To be saver - the auto-update logic does the update only after a number of fails for not breaking links in single fail situations that could really happen because of server down and other technical issues on remote hosts.

Sounds like the developers of this site need consulting - what HTTP status codes are for and how they work - I'm open minded to offer a beginners session to them if for interest.

@hass
thanks for your time and the explanation