[askwhy]

This can happen if you are launching Opera from one of the originally pre-filled spots on the top of the 'Programs' tab of Manila (the 4 or 5 default shortcuts). The variables that were being used for the original Icon/Program are now being passed to Opera as if they were a URL. For example, the 'slot' originally holding the icon for 'People' went to the Manila 'People' tab by passing a --switchtopage variable to Manila. Other programs besides Opera put in those same top slots tend not to care about the extra variables being passed their way, but Opera throws the page load error like the one that you are seeing.

I am not sure off the top of my head what registry or other setting(s) are retaining the old variables (I don't use the programs tab). Something needs to be adjusted to prevent this, but as a workaround you can make sure you have put Opera in a different slot on the Programs page. Any slot that didn't previously have a shortcut to a Manila page/function (or one that was originally empty) will probably work fine.

Anyways, I assume from your screenshot that this is your issue, but if it isn't, please disregard.