Hints and troubleshooting & Displaying program information

Displaying program information

Display program version

pdfToolbox --version

will display the currently used version of pdfToolbox CLI.

Display usage information

pdfToolbox --help

will give you a complete overview about all available commands for processing.

pdfToolbox --help <command>

will give you an overview about all available options for the command.

Display status

pdfToolbox --status

will inform you about the current license state as well as the possible return and reason codes (see "Results").

Hints and troubleshooting

Ensure sufficient free disk space

To ensure stable processing, it is recommended to have at least 4 times of the input file size of processed files available for intermediate file system storage (e.g. /tmp on Unix and similar on other systems).

Avoid stopping workflows on Windows

On Windows, you can prevent your workflow from stopping in case of a pdfToolbox CLI crash by setting the following registry entry:


If ErrorMode is set to "2”, crash dialogs will be suppressed. For further details, see: http://support.microsoft.com/kb/128642/en-us?fr=1

Limiting the maximum memory used by pdfToolbox

Using Linux, you can limit the amount of memory used by a single process by an additional parameter:

--maxmemory=<max. memory in MB>

Processing will stop and result in an error if memory is exceeded.

Limitation of concurrent processes

If the StdOut of the command line indicates "Maximum number of parallel processes allowed by license already running; waiting until one of the current processes terminates" (before pdfToolbox 10: "Waiting for CPU"), the maximum number of parallel processes is reached. A default Server/CLI license allows up to 8 parallel processes. To run more than 8 processes simultaneously, you should look at callas License Server as the better option. You can find more info here.

Performance enhancement

If you want to enhance the performance of your pdfToolbox CLI processes, please keep in mind the following rules:

• For analysis, you can limit processing to a certain page range (see "Only process certain pages").

• Rather remove fixups from a profile only intended for analysis than using --analyze (e.g. when using --analyse, initialization of ICC profiles for color conversion fixups still takes place).

• Fixups containing an "Apply to” option need more processing time if this option is set to something else but "None”, since an analysis of the file contents is required before the fixup can be executed.

• If you are using any font embedding fixups, your system font folder will be scanned unless defined otherwise in the fixup configuration. A font cache will be created to improve the performance time, but still it might be useful to remove fonts that are not needed from this directory.

• Keep in mind that the option --uncompressimg (see "Analyze image data") will uncompress images and analyze every single pixel, which may take a long time for some files.

• Creation of XML or PDF reports takes less time than the XSLT option

(see "Report types").

• Creation of reports takes additional time – even if a profile contains only fixups, an analysis will be executed for gathering report information.

Optimization of needed installation space

To reduce the space needed by the installation of pdfToolbox, it is possible to delete some subfolders of the CLI component (in subfolder /cli) if their respective functions are not needed in the individual use case.

To avoid processing errors or unexpected behaviour of pdfToolbox any modification should be done well-considered.

If no Arrange action is used
If no font embedding or PDF/A conversion is used (or if font situation is clear)
If no layer/image mask report is used
If no preflight certification is used
If no color conversion is used
If no PDF report based on HTML template is used
If no inventory report is used
If no Office-files are processed
If no PostScript-files are processed
If no PDF/A-HTML Report or ZUGFeRD is used
If no archive files are processed
If no Comparison is used

Install basic fonts on Linux

As most Linux distributions are delivered without or with very few fonts, it is advisable to install at least a basic set of fonts.
We recommend installing at least the the fontconfig package ant the MS core fonts, which is e.g. done on Debian-based distributions by the following commands:

sudo apt -y install fontconfig

sudo apt install ttf-mscorefonts-installer

For other distributions, please consult the respective documentation.

Possible errors within the Server-UI communication

The communication between the Server-UI and the underlying Server process (which observes the folders) takes place by network communication ports using SOAP.

When the Server-UI shows a warning for a connected Server like "Error 28", it indicates that  there were errors either during the connection to the Server process itself or that the Server process has stopped working.

You can try to reconnect to the Server in the UI or try to start the local Server process again by the "Start Server" option.

How to use pdfToolbox CLI: