Hello: I am having a problem in a project. In track view, some tracks don't show waveform, but instead show piano roll. The curser becomes a magnifier when moved over theses tracks. In fact, every new track I add to this project is displayed in this form. Seems to be related to the PRV tool. Can anyone direct me to the solution? Thank you.

Which version are you working with?
Are you inserting MIDI tracks? These will not display a waveform.
Audio tracks will show a waveform.
Simple Instrument tracks are hybrid and may show either/both.
Give us some details on the particulars of your project.

Those are MIDI tracks. Sonar has 2 types of tracks, audio and MIDI. You should read the Getting Section of the Help Menu. There's a lot of good information in there. 

Version 7.0.1.120 I apologize. I did not correctly describe the problem I have with this project. In track view, when I use Dimension, DreamStation, Dyad, RXP, or another soft synth, I normally would see a solid colored bar and a representation of the notes for the track. If I double click the track I would see a large piano roll for that track. With this project, rather than a colored bar in track view, I have a mini piano roll for each soft synth track. When I place the curser over the mini piano roll for the track, that area is magnified. Audio tracks display normally. I opened several previous projects and started a new one, and in each case, adding a soft synth track resulted in a mini piano roll being displayed for the track instead of a colored bar. Seems to have something to do with PRV. Thank you.

I finally figured it out. From text menu - Tracks - In-line PRV - PRV Mode. Unchecked PRV Mode. That was all it was. Somehow it switched to PRV Mode??? I appreciate your interest in helping me solve the problem.