Cleaning Up PDF Documents
Not all PDF files are created equal. The way in which a PDF document is generated makes a difference, and PDFs generated by third party tools in particular can vary in quality. PDF documents can also become corrupted.

To check how the file was created:
In Acrobat 6, select File > Document Properties… and click Description. Under PDF Information, look at PDF Producer.
In Acrobat 7, select File > Document Properties… and click Description. Under Advanced, look at PDF Producer.
In Acrobat 8, 9, and X, select File > Properties… and click Description. Under Advanced, look at PDF Producer.

If the PDF Producer field is blank, consider the file suspect.

Making a Clean PDF
If you are having problems with a specific PDF, try to create “clean” version of your document. There are two ways of doing this using Adobe Acrobat. If you use other PDF manipulation software, check the documentation for functions that may be equivalent to those found in Adobe Acrobat.

Method 1: “Optimize” your PDF
In Acrobat 6 and 7, select Edit > Preferences… and click the General Category, then check Save As optimizes for Fast Web View in the Miscellaneous section.
In Acrobat 8, 9, and X, select Edit > Preferences… and click the Documents Category, then check Save As optimizes for Fast Web View in the Save Settings section.

Select File > Save As. You can save over the original file or give it a new name.

Acrobat 6 and later includes the ability to optimize all PDF files in a directory at the same time using Batch Processing.

In Acrobat 6 and 7, select Advanced > Batch Processing… and run the Fast Web View sequence.
In Acrobat 8 and 9, select Advanced > Document Processing > Batch Processing… and run the Fast Web View sequence.
In Acrobat X, you’ll create an Action to optimize a directory of files. Refer to Acrobat’s on-line help system for more information.

If saving as optimized does not work, distill the document by following the steps below.

Method 2: Distilling PDF Documents
Distilling a document will remove all comments and form-fields from the PDF. If the PDF contains these items and you wish to preserve them, you must save them before Distilling.

To save existing comments

In Acrobat 6, select Document > Export Comments… In the Export Comments dialog box, select a name and location for the Forms Data File (.fdf), and click Save.
In Acrobat 7, select Comments > Export Comments > To File… In the Export Comments dialog box, select a name and location for the Forms Data File (.fdf), and click Save.
In Acrobat 8 and 9, select Comments > Export Comments To Data File… In the Export Comments dialog box, select a name and location for the Forms Data File (.fdf), and click Save.
In Acrobat X, select Comments > Comments List > click the Options icon > Export All to Data File… In the Export Comments dialog box, select a name and location for the Forms Data File (.fdf), and click Save.

See the additional step below for saving form fields (if any):

Delete all comments:

In Acrobat 6, 7, 8 and 9, select all the comments in the Comments pane and click the Delete icon on the Comments tool bar.

In Acrobat X, select all the comments in the Comments List pane and press the Delete key.

To save form fields (if any):

Save a copy of the original file. You will copy and paste the form fields from the original file into the new file after the distilling procedure.

Distilling the document

To distill a PDF document do the following:

In Acrobat 6, 7, 8 and 9, select File > Save As… (In Acrobat X, select File > Save As… > More Options > PostScript.)
In the Save As dialog, choose PostScript (*.ps) for the Save as type.) Choose a name and location for the file and click Save.

Choose a name and location for the file and click Save.

Open Acrobat Distiller (In Acrobat X, select Tools > Print Production > Acrobat Distiller).

In Acrobat Distiller, select File > Open… In the Open PostScript File dialog, locate the PostScript file created in the previous step and click Open.

The distiller will create a new PDF file with the same name and location as the PostScript file.

Restoring comments

To restore the comments:

In Acrobat 6, select Document > Import Comments… In the Import Comments dialog box, locate the Forms Data File (.fdf) previously saved and click Open. The comments are restored.

In Acrobat 7, 8 and 9, select Comments > Import Comments… In the Import Comments dialog box, locate the Forms Data File (.fdf) previously saved and click Open. The comments are restored.

In Acrobat X, select Comments > Comments List > click the Options icon > Import Data File… In the Import Comments dialog box, locate the Forms Data File (.fdf) previously saved and click Select. In the next pop-up box, click Yes. The comments are restored.

Restoring form fields

To restore form fields:

Open the original PDF file that includes form fields.

In Acrobat 6, 7, 8 and 9, select Tools > Advanced Editing > Select Object tool.
(In Acrobat X, select Tools > Forms > Edit Form)

The form fields will appear, do a Control-A to select all the form fields.

Open the new distilled PDF file which has no form fields.

Do a Control-V to paste all the form fields onto the page.

You may need to reposition the fields by selecting them again with the Select Object Tool and moving them to the correct position. For multi-page forms you must do this for each page separately.