Unable to edit PDFs in Adobe Acrobat 8. Why?

I have just received a large number of PDFs from a client who has asked me to make some layout changes to the documents. I informed told him that I am still a novice at Acrobat, but I have created/authored PDFs in the past and found it rather simple. Since already I've used the PDF editor to build documents similar to what my client was asking for, I assumed it would be easy to make the minor layout changes he requested.

Unfortunately I cannot seem to edit these PDFs at all! I've double checked the accessibility/security features of the documents and they are fully accessible with no editing restrictions. I am also able to copy/paste text from the PDF into Word, so the PDFs are definitely not rasterized images.

I've never actually tried to edit a PDF that was not created by me before. I am starting to think that once a PDF is created and saved, you lose the ability to edit it!

Why am I unable to access any of the editing tools that I would normally have when creating a PDF document? I need to be able to insert images, rearrange text and add a few lines and boxes with drawing tools.

Could someone please help direct me in this matter?

Thanks

 

So I managed to open the PDFs in LiveCycle Designer. Is this the proper way to go about editing a PDF?

It doesn't seem right, somehow. Every bit of text is blocked off into it's own little box. Columns and paragraphs go unrecognized. It's very chopped up...

Is it likely that the PDFs sent to me were originally created in another program and then converted to PDF? That is the common way of making PDFs isn't it? You design the document in Word or Excel, and then convert it to PDF, right? If so... it's likely that all these PDFs have a source Excel file... that would probably be easier to edit than re-convert...

 

I'm just going to go ahead and ask this question here as well: Is there a way to determine the source document that a PDF was created from?

For instance, if an Excel file was converted to PDF, would the fact that the original document was an .xls file be accessible from the PDF file?

 

I know I've replied to myself several times already... but I still have some issues and would appreciate some direction if anyone can offer it. Thanks.