I tried to find solutions and found some solutions for similar problems, but there were not suitable solutions for my case.
In my case, some pptx files could preview in alfresco but some pptx files could not preview with "could not load pdf content" message.
I can't find differences among pptx files.
I guess it doesn't related file size because some files are well-previewed even though they have bigger file size.
1. Some pptx files are well-previewed(= could preview in alfresco), but some pptx files could not preview in alfresco.
2. Error Message : "could not laod PDF content"
3. I doubt file size issue, but some bigger size files are well-previewed. I guess this situation has not file size issue.
4. Maybe LibreOffice libraries are well included, because some pptx files are well-previewed in alfresco.
How can I fix this error?