Sometimes PDFCreator Creates Files with Incorrect Extension



In this example we are going to perform Function Testing on the Print to file function of PDFCreator. Our goal is to make sure that the application is able to print the selected content to a file type specified by the user. PDFCreator is a software printer that can print any document to a PDF or image file. The problem is that the output files generated by it have .pdf extension by default, even if the user selected them to be image files.

Application Description

PDFCreator provides graphical user interface for Ghostscript and some additional features as well. It creates a software printer, so when the user prints to it, the output file will contain the same information as if the document was printed to a physical printer. (Source:

The output file can be a PDF, postscript (.ps), or image (.jpg, .bmp, .pcx, .png, .tif) file.

Test Design

This example demonstrates the use of Function Testing.

These are all the possible formats for the output file. For this test we will focus on the functionality related to printing files to image files (JPEG for example).

We would create a word document and then print it to the software printer created by PDFCreator.

We would expect that if we save the output as a JPEG output file, it will contain all the information that a printout from a physical printer would have.


Performing the Test

  1. Start any application that is able to print (Word for example).
  2. In the dialog box that appears select PDFCreator. Click "OK".
  3. We can enter any additional information about the file in the dialog box that appears. For example we can set the document title to 'test'. Click "Save".
  4. Now we can apply the test by selecting a .jpg file type for the output. Notice that the default filename is the name we entered in the previous dialog plus a .pdf extension.
  5. Even though we selected JPEG output type, the filename still has a .pdf extension. Press "Save".


PDFCreator created test.pdf as an output file even though we selected JPEG output file. The file is not readable by Adobe, and after opening it with MS Paint it turned out that PDFCreator really created a JPEG file but put the incorrect extension (.pdf). The problem can be avoided by manually changing the extension in the save as dialog box or by renaming the output file.

Users would expect that changing the type of the output file will change its extension also. Some of them might not notice that the file is going to be saved with the wrong extension, and will get the impression that instead of creating a JPEG file, the application created a corrupted PDF file.

Similar Tests/Additional Notes

We can try the same test with other image types. The results are the same.


Testing PDFCreator v0.8.0[2] on:

Created 25 May 2004 for the CSTER

All images and written material ©Copyright Georgi Nikolov 2004

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