Teknoids

I fully appreciate that this request for assistance may not be 100% within Teknoids' jurisdiction, but I am desperate. For some reason completely unknown, my iMac G5 2.4 GHz Intel Core 2 Duo (running OSX 10.5.6) has very recently suddenly ceased being able to download anything whatsoever from the internet. I can access the web OK, send and receive email OK etc, but all attempts to download anything at all fail. Nothing whatsoever happens when I click on any "Download" link anywhere on the internet. No spinning wheel, nothing happening in the "Download Activity" window. Absolutely nothing. Can any helpful person suggest a possible reason for this ? Are there any files that I should specifically be checking on my Hard Drive  -  i.e. files that are essential for downloading to work ? If so, please advise and I shall see whether they are missing, corrupted or whatever. ANY help whatsoever would be greatly appreciated. I am at a loss at present !!Thanks !!Ron Huttner LL.B (Hons)(Retired) Barrister, Solicitor, Law Lecturer and Legal ResearcherMelbourneVictoriaAustralia