Since updating to Acrobat 11.0.7, the electronic signature function has broken. Users receive an error message when trying to insert an electronic signature "There was an error when attempting to commit this signature. The document was not saved. The file may be read-only, or another user may have it open. Please save the document with a different name or in a different folder. The document could not be signed. HFT error. This file is already open or in use by another application."
Error occurs even after saving the PDF locally and renaming. This issue is affecting multiple users and has never occurred in previous versions of Acrobat installed. Temporary workaround is to rollback users to Acrobat 11.0.6.