Kerio Auto Adapter and Compaq Computer

Well, if the internal battery requires 18.5V to charge it then 18V won't do the trick.
If it was my Compaq I'd try 19V and see if things get too hot anywhere.
But, its your computer and your risk ;-)

Klaus

A lower voltage shouldn't harm anything.....
A higher voltage might- but then when you're only talking half a volt, I don' think it too much of a concern.
I'd try the low voltage first.

A couple of thoughts:

Measure the actual voltage put out by the adpter at both settings in case they're not exactly 18.0 and 19.0 - you may be lucky and one of them is close to 18.5.

Check the voltage being put out by the 240v adapter and match this (again it may not be 18.5) I have assumed in both cases that they are switch mode power supplies and will show the same voltage with and without load.

As a previous post said, it's unlikely that a lower voltage will do any harm but if too low either the computer won't run or the battery won't charge (or both)

Adrian