saving as pdf

Yes.

 

By @Lyn27318678mcs2

Then, you have provided one of the valid pdf formats.

Second way to verify:

Can you open the provided file in Elements or photoshop directly, without the conversion dialog at start ?

If so, that would mean that you have used 'save as' with the option for the format 'Photoshop PDF...' which is the only one available for Elements.

That flavour of pdf is a container holding a true 'Acrobat' PDF format AND a true PSD format, so it can be opened either with Acrobat (or Illustrator, Indesign...) or with PSE or Photoshop while keeping all the properties of the original file, including layers, text, shapes layer components.

Huge advantage for versatility, at the cost of a much bigger file size. This Photoshop PDF format is recognized by the organizer and can be managed like a .PSD or a .TIF.

If you want to create a simple PDF format from Elements, use a virtual PDF printer driver like the one provided by Windows (Print to PDF). You don't save, you 'print' virtually into a true Acrobat PDF format, even with multipage PDF from printing several files at the same time. The sad result is that the true PDF format is no longer supported in the organizer since a number of PSE versions.

Supply this true Acrobat version to your printing service and ask them what software they are using with PDFs and their requested PDF versions.