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Im helping a relative who is having difficulities with access to the internet at the moment on a windows vista pc in every browser type. I can both ping websites (ip/dns) and access https versions af websites on the pc but can not find any reasons to why port 80 websites are not loaded. On some of the pages i can see it downloads the title of the webpage and then it just stops. I can not find any errors in windows defender og windows firewall. Have tried disabling them to see if that helped but nothing happened.

Any ideas?


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This sounds like a malicious proxy has been setup. If you can ping a website ( I assume it returns the correct ip address ) but cannot access the website thats a problem. I would do a full format of the hdd and reinstall Windows. – Ramhound Oct 25 '11 at 13:11
up vote 2 down vote accepted

This may be an MTU issue.

Depending on what connects you to the Internet (Router, USB-'modem' etc..) you might need to adjust the device's MTU value. Have a read:

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Thanks it worked :) Any clue why this can happen on a connection that previously worked – dcasso Oct 25 '11 at 13:22
Glad you got it fixed. Can't really say what's happened to make it suddenly stop working - ISP may have changed the line parameters or some of their kit, could be a recent s/w patch on your OS...?? – Linker3000 Oct 25 '11 at 19:49

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