Can you try using a different browser and let us know if you still face this issue?
Same error message in Firefox and Chrome.
I'm more interested in solving the Html5 conversion problem.
Since you are not able to report the bug, can you please share your content using any file sharing services(such as Dropbox, etc). We can look at the content.
This bug doesn’t appear to be triggered by any specific content within a file. Each time a conversion has failed, running the command a second time (or third time) has been successful.
As with the ‘Distribute to Layers’ bug that was introduced in Flash CC 2013, it looks like Flash occasionally gets into a state where attempting to do an Html5 conversion will result in the appearance of this problem. I haven’t been able to figure out the steps that cause Flash to get into this state.
If you search this forum, you’ll see other reports of the ‘Embedding OLE objects’ error. In every case, the error occurs when content is being pasted to the stage via a command.
Just happened to me.