This applies to OneNote 2003 and possibly OneNote 2007

In OneNote 2003, some people have experienced a situation where ink simply disappears after writing in OneNote. It's there for a few seconds, then it vanishes. Sometimes this is the result of accidentally hitting the pen button while drawing, but here is the explanation for a less obvious cause:

This is sometimes caused by accidentally turning on the "use pen as pointer" tool. This is a tool that lets you make temporary marks on a oneNote document for the purpose of highlighting or identifying something on the page. After a few seconds, the mark will automatically disappear.

To access the controls for this tool, do the following:

1. Open the writing and drawing toolbar by going to View, Toolbars, Drawing and Writing Tools
2. On this toolbar, are two pen tools. One has a solid line below the pen, the other has a line that fades to gray. The icon with the fading line is the "use pen as pointer" tool. If it is activated, you are probably experiencing disappearing ink.
3. To de-activate this tool, simply click on the regular pen tool in the Drawing and Writing toolbar. This is the one with the solid line below it.