Extra white space beside document??

This one has been asked before ... but the suggested fixes don't work for me.  This is a mockup of the extent of the white space.  It shows on the thumbnail, but there's nothing visible in the document itself.  I've done a wireframe view - nothing.  Selected an area larger than the page - nothing.  Have reset the workspace a few times to no avail.   Sometimes I can select just the page and paste in a new document and it fixes, but usually not. 

In the past I thought it was somewhere in the process of exporting to jpg - because that's where I first encountered it.  But today the penny's dropped.  It's in the original.   Never learned or did Corel professionally, just worked things out as they happened.   And learned new things when somebody wanted something different.  But the technical side occasionally gets me beat.

Any advice would be much appreciated.