The first thing I suggest is to run all your malware utilities.
A strange problem has just occurred with Firefox. When I try to open it I get the message 'The connection was refused when attempting to contact the proxy server you have configured. Please check your proxy settings and try again' This is confusing, because I have not, to my knowledge altered anything from last night when the beowser worked perfectly. It may be something simple, but I cannot understand it.

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