In Adobe Connect product:
As a presenter I have uploaded powerpoint presentations to be able to show them.
Is only for me available? Can an Administrator access my powerpoint presentations?
Because I want to protect my presentations of distribution.
If you upload the presentation, the Admins could technically find it and pull down the source file. While not an easy or common practice it can be done.
If you really want to avoid that, just use screen sharing and put your PPT in presentation mode. Then the file never gets uploaded.