Are you browsing the site www.imf.org when the error happens? Go to your command line and run an nslookup to see if your DNS is resolving properly on the machine. It should look like this:
C:\Documents and Settings\scott.SCOTT>nslookup www.imf.org
Server: dns.apexsoftware.com
Address: 10.2.1.4
Non-authoritative answer:
Name: www.imf.org
Address: 204.180.229.21
sknake
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