I have had a user who informed me she could edit a signed PDF's on Adobe Acrobat Standard Version X
Since our upgrade to Adobe Acrobat Standard Version XI she cannot edit signed PDF's
I have tried with both versions and I was unsuccessful at editing signed PDF's
Could you please explain what exactly are you trying to perform?
Please explain the workflow.
What exactly are you experiencing while trying to edit a PDF?
How are you trying to edit the PDF?
I hope the PDF is not protected with a certificate.
What OS do you work on?
That's expected behavior. When you sign a PDF it prevents it from being edited (except for form fields, if you allow for that). That's one of the main reasons to use a digital signature: It assures you that the file is not edited in any way after you signed it.