New
#21
The ultimate solution
Every attempt to correct the problem failed, so I decided to hit it softly with a sledge hammer: Do an "upgrade" to a new Windows 7 image without interfering with user files data as described in sevenforums' Tutorials.
Since my original Windows 7 load disc had been superseded by Service Pack 1, I downloaded a new W7 SP1 ISO file, wrote it to DVD and then loaded it. My first check was the IE problem: joy-oh-joy the problem had gone:). Opening a page in a new tab was fixed. However, it wasn't long before things started going wrong. Half of my applications caused a BSOD when launched. Always related to a nVidia sys file paging problem. Upgrades, downgrades and any other grades failed to make an impression.
In the end I bit the bullet and did a full backup of all user data and then did a clean reload of Windows 7 SP1. All my problems have now gone away, apart from the fact that I've lost many, many hours of my life over the past 3 weeks trying to fix what appeared to be a relatively small feature problem.
What would I do if the problem occurs again? I'll install Firefox or Chrome after disabling IE. And never waste my time doing an W7 upgrade, thinking that could solve a W7 problem.