>Wow, the only way I have found to gain scrollbar vertically on IE, was to force it like these:
>
>@-ms-viewport{width:auto!important}
>
>It appears the bootstrap css file overwrites that. Anyone knows something about this?

Bootstrap:

@-ms-viewport {
  width: device-width;
}

But your setting should override that? Not sure why it's there though. See: https://msdn.microsoft.com/library/hh869615(v=vs.85).aspx

Also don't see why a width setting would affect the vertical scroll bar (I assume you are referring to the browser scroll bar rather than any on elements of the page?)