Introduction
Spindle Professional generates PDF files with encryption to prevent the file being modified. However, the level of encryption can cause issues with PDF viewers that don't recognise encrypted PDF files, thus prompting the viewer for a password. AES-256 encryption requires Adobe Reader v9.0 and newer to negate the prompt for a password. If you are unable to change your PDF viewer to Adobe v9.0 or newer, Spindle can render the PDF using AES-128 encryption by using an older PDF creation library.
By default Spindle Professional v6 generates PDF documents that comply with v1.7 of the PDF standard with Adobe level 3 Extensions. This standard requires Adobe Reader v9.0 or higher or a compatible viewer to open and view them. Use of this standard allows Spindle Professional v6 to secure documents using AES-256 encryption.
| Software | Version Tested | AES-128 | AES-256 |
| Adobe Reader | 9.0 and newer | OK | OK |
| Foxit Reader | 6.2.3.0815 | OK | OK |
| Nuance PDF Reader | 8.1 | OK | OK |
| Sumatra PDF | 2.5.2 | OK | OK |
| PDF Complete | 4.1.45 | OK | NO |
| Nitro Pro 10 | 10 | OK | OK |
Versions Applicable
- Spindle Professional 6
Prior to following the resolution below, please try the resolution specified here: Use Legacy Encryption
Resolution
1. Open Spindle Professional Tools
2. Expand the Document Automation until you see Email Settings
3. Click on the Advanced tab
4. Select the default attachment type to PDF
5. Drop down the PDF creation library from Default to v3.5.0.101
Documents will have to be processed again for the changes to take in effect.