Did a bit more research on this.
Despite solving my bank access problems (temporarily as it turned out) I still had problems with character omissions, inactive carriage returns etc. on the Forum. I un-installed IE11, un-installed IE10 too and went right back to IE9. Then a fresh re-install of IE10 after first getting all necessary Windows updates that it required.
Character problems were still there. I never had them previously with IE10, so what I suspect happened was that IE11 changed some vital settings when it installed itself, and those settings have remained in place to affect any version of IE that I now install. Worse still, I could not even access my bank's logon page, let alone enter logon details. My previous trick of disabling some Kaspersky features, did not solve the 'bank access' problem. This was Commonwealth Bank of Australia's Netbank that I was having trouble with.
I note a couple of significant things here; I could access and logon to Netbank OK using Chrome as the browser, which proved the Netbank page was active. And even from my semi-crippled IE10, I could access an account I have with another bank, ING. I took this all to mean there was some subtle incompatibility only between IE (or its settings) and CBA's Netbank.
I should mention here too that I did try IE's 'broken page' compatibility icon, but it made absolutely no difference.
After a further day Googling for hints I discovered that someone else had pretty much the same problems as me, except it was with Bank of America's internet banking. The advice from a sage at Microsoft said that some banks had been slow to upgrade their encryption protocols (or something like that) and suggested un-checking the "Use TLS 1.2" option, buried deep in IE's advanced security settings. Did that, and suddenly I could access my net bank once again. How securely, I don't know, heck I don't even know what a TLS is.
In theory, I suppose should be able to upgrade to IE11 as long as I take note of all my settings and restore them if something doesn't work, but I'm feeling exhausted by the experience so I think I will stay with IE10 for now (and make sure I un-check its "install new versions automatically" box in the "About" menu.
And I still have the problem with WYSIWYG text on vBulletin forums (or at least Trainz forums), so I'm not impressed with IE11 (or IE10 for that matter). But habit keeps me using the damned thing!
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