I have to admit that I have been running out of ideas why the wiki cannot get a connection
while "curl" can.
One last try: has the gateway connecting the local network to the internet an application
firewall or the like ?
Something that sniffs user-agents for http connections and only allows "known
ones" ?
The java client used by the XWiki installation wizard might be emulated with:
  curl --user-agent "history" 
http://extensions.xwiki.org
if this works, too, I have to admit I have no clue why it does not work.
(Btw, there should be an error message in the log files. Is there anything like that?)
Clemens
----- Ursprüngliche Nachricht -----
From: Frank Thommen
On:  Saturday, 23.01.2016, 16:13
To: XWiki Users
Subject: Re: [xwiki-users] XWiki 7.4 Distribution Wizard says: "We couldn't find
any extension with id 'org.xwiki.enterprise:xwiki-enterprise-ui-mainwiki' and
version '7.4'."
  On 22.01.16 15:12, Clemens Klein-Robbenhaar wrote:
 some random ideas:
   - in WEB-INF/xwiki.properties: are any settings for extension.repositories=...  enabled
     or are they all commented? 
 They are all commented
 There are only the following - commented - settings:
 $ grep extension\.repositories xwiki.properties
 # 
extension.repositories=privatemavenid:maven:http://host.com/private/maven/
 # extension.repositories.privatemavenid.auth.user=someuser
 # extension.repositories.privatemavenid.auth.password=thepassword
 # extension.repositories=local:maven:file://${sys:user.home}/.m2/repository
 #
extension.repositories=maven-xwiki-snapshot:maven:http://nexus.xwiki.org/ne…
 #
extension.repositories=maven-xwiki:maven:http://nexus.xwiki.org/nexus/conte…
 #
extension.repositories=extensions.xwiki.org:xwiki:http://extensions.xwiki.o…
 # extension.repositories=
 $
 I will try with uncommenting the two proposed defaults next week.
      If I uncomment just a lone
'extension.repositories=' I get exactly the error in the screenshot
   - Another idea: any chance there is a name resolution problem on the server?
      
extensions.xwiki.org should resolve to 5.135.240.206 (currently) 
 works fine:
 $ host 
extensions.xwiki.org
 extensions.xwiki.org has address 5.135.240.206
 $
       "curl 
http://extensions.xwiki.org"
-> should return a 302 to the Start page 
 fine, too:
 $ curl 
http://extensions.xwiki.org
 <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
 <html><head>
 <title>302 Found</title>
 </head><body>
 <h1>Found</h1>
 <p>The document has moved <a
href="http://extensions.xwiki.org/xwiki/bin/view/Main/WebHome">…
 </body></html>
 $
 frank
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Clemens Klein-Robbenhaar
--
Clemens Klein-Robbenhaar
Software Development
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