Originally posted here by zebo50

R1 - HKCU\Software\Microsoft\Internet Explorer,SearchURL = http://www.isearch.com/index.php?app...DQ6NTo5&Terms=
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.isearch.com/index.php?app...DQ6NTo5&Terms=
R1 - HKCU\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://www.isearch.com/index.php?app...DQ6NTo5&Terms=
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://www.isearch.com/index.php?app...DQ6NTo5&Terms=
O2 - BHO: (no name) - {2A646672-9C3A-4C28-9A7A-1FB0F63F28B6} - C:\PROGRA~1\IDA\idaiehlp.dll
O4 - Global Startup: KYESCAN.lnk = ?
O8 - Extra context menu item: Download ALL with IDA - C:\Program Files\IDA\idaieall.htm
O8 - Extra context menu item: Download with IDA - C:\Program Files\IDA\idaie.htm
O9 - Extra button: Internet Download Accelerator (HKLM)
O9 - Extra 'Tools' menuitem: &Internet Download Accelerator (HKLM)
Lotta stuff in there. The download problem probably stems from

O2 - BHO: (no name) - {2A646672-9C3A-4C28-9A7A-1FB0F63F28B6} - C:\PROGRA~1\IDA\idaiehlp.dll

I would suggest removing the ones I have quoted also.

You can delete all of the O16 section also to clean things up, as these are just applets that are downloaded to your machine.

EDIT: Just checked on google. IDA is internet download accelarator. Remove all the entries that have IDA in them.

Lotta editing involved. IDA is the culprit.