Adobe PDF Pack Conversion Problem

[richards25630555]

I created pdfs with adobe acrobat reader DC.  I bought the Adobe PDF Pack to combine PDF's but when I go to combine them it says conversion failure due to password protected, encrypted protected or doesn't support file type.  How can I merge these files?  Does Acrobat Pro DC merge all pdf types or would I have the same issue?

[Test Screen Name]

It won't ignore security on files. Did you check the security? File > Properties; Security tab. Method must be NONE.

[richards25630555]

It says "No Security"  under method.