Firefox was working on my new iMac but then, after switching on recently, won't connect to the web – whereas Safari has no problem.

Question

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Hi
I bought an iMac a week ago and installed Firefox via Safari. It worked fine for a while but, after a recently switching on, it won't connect to the web whereas Safari has no problems.
I've tried following the Firefox Help, looking into the iMac firewall, but still no luck.
I've no idea whether related or not but yesterday I had a system glitch where the iMac stated no wi-fi was installed and only connected via a physical lead to my house router. Also, there was no sound output via Safari. However, after booting up today all seems well – apart from Firefox still not working. It loads the start page but can't access the web.
I have Little Snitch running, and wonder if that's the culprit... but it's working fine with Safari, seemingly.
(Finally, how do I stop a dialogue box appearing on start-up saying that "To open “X” you need a Java runtime. Would you like to install one now?)
Any ideas anyone?
Cheers
Rob / Sheffield / UK
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Answer 1

On the wireless networks that your Mac has had trouble connecting to, do you know which Wireless Security type (WEP, WPA, or WPA2) is being used?
If it is WEP, one of the problems is that the actual standard relies on a 10 character HEX key for 40bit WEP and a 26 character HEX key for 128bit WEP.   In order to make things easier, vendors use certain algorithms to convert simple alphanumeric passwords (or passphrases) into HEX keys, thus enabling the use of simple easy to remember WEP password rather than lengthy HEX keys. The problem is that different vendors use different algorithms to generate the HEX key and therefore a ASCII password on an AEBS will be hashed differently on a non-Apple client and vice versa.   You may find the following Apple Support article helpful.