EverCam is truly easy to use for everyone who wants to record PowerPoint lectures. Just click the EverCam Record button on the Quick Access Toolbar in PowerPoint. It functions like the Slide Show button but with recording capability. The slide show will begin, and EverCam will record the instructor’s webcam, voice, screen, and cursor movement.
During the slide show, give the presentation as usual: show animations, change slides or make annotations. EverCam will help create a chapter marker for every slide you present, and thus make video editing and navigation much more efficient.
When the presentation is ended, for example by the ESC key, EverCam will also end the recording; the video tutorial is completed at the same time.
EverCam is not limited in PowerPoint. It’s a standalone screen-recorder. Anyone can use it to create video tutorials of any sort.   Learn more >
When you start recording again in the same PowerPoint file, EverCam works like a tape recorder: it appends the newly recorded content to the previous content. As a result, you’re not required to do any video editing even if the presentation has been recorded separately at different times. The contents are always combined and made as a complete, uninterrupted video.
How to delete the unwanted video clips?
Open the EverCam editor. You’ll see the chapter markers created by EverCam. Select a chapter marker and hit Delete. It’s just that simple!
In the editor, you can also rename, split, import, and export clips or change their order. Or use the advanced editor to record narrations and adjust volume.
Therefore, re-recording slides is very easy: delete an unwanted clip and replace it with a newly recorded clip.
Use the Upload on the EverCam menu to share the videos directly to YouTube or Camdemy.com
Camdemy offers not only free storage, but also numerous wonderful features designed specifically for online learning.
You finally finished the recording but found a small mistake in it, or you would like to insert a video clip and add annotations. EverCam Point can take care of it for you. 
EverCam Point enhances the capabilities of EverCam for video post-production. It helps integrate EverCam videos, add annotations, create animations, apply themes, etc. It's easy to use and empowers everyone to create professional-looking online courses.