When I’m working in Normal view, I see all the slides. But during the presentation, some slides are missing.

Those slides are probably marked as hidden. You hide a slide by clicking the slide in one of the various views (such as Normal or Slide Sorter) and clicking the Hide Slide button on the Ribbon’s Slide Show tab. In Normal view, it’s easy to spot hidden slides because they appear with a lighter shade in the pane on the left side of the window. In Slide Sorter view, they’re harder to recognize. The only indicator is a little slash mark through the number below the slide. To unhide a slide, choose it and click the Hide Slide button again or right-click it and choose Hide Slide.

During a presentation, you actually can open a hidden slide by right-clicking and choosing Go To Slide. The hidden slide appears on the pop-up list with parentheses around its number. Click its name to show the slide on-screen.

I copied my slideshow off a flash drive onto the meeting room’s computer. But when I try to open the slideshow in PowerPoint, a message says it can’t open the file.

When I connected my notebook computer to the audio/visual system in our office’s conference room, I saw the active presentation on the podium’s built-in monitor and a preview of upcoming slides on my notebook screen. Now I have a projector plugged directly into my notebook computer, and I can’t find that view option.

When you were running two monitors with your computer (counting the computer’s built-in LCD), you had access to Presenter View. It’s a handy tool that lets you constantly preview what’s coming up in the next slide, watch the presentation timer, and more. If you’re running a projector directly from your computer, however, this view is unavailable. (To confirm whether your computer supports this view, click the Use Presenter View box on the Slide Show tab and click the Check button to let PowerPoint examine your computer’s capabilities.)

I used the Advance Slide feature on the Animations tab to set several slides to advance automatically after three seconds, but the slides don’t advance when I run the slideshow.

PowerPoint allows you to turn off slide timings. To see if this happened, click Set Up Slide Show on the Slide Show tab and check whether the button marked Manually is selected under Advance Slides. For timings to work, select the button marked Using Timings, If Present.

I see a lot of confused faces in the audience when I put up some of my slides.

If we assume that you’re not just a confusing presenter, the problem could be your slides’ readability. Many slides are packed with text and images that are too dense or small. It’s easy to miss this problem when you view slides only on a computer screen in front of you. Always test your presentation on a full-sized screen. Try viewing the slides from the back row of a room like the one in which you’ll be speaking. You’ll often realize slides could use a more readable font or color palette or just some simplification.