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Higher editions of VPE offer types and properties of objects, which are not available in lower editions. Therefore higher editions can read document files which have been created with lower editions, but it is not possible to write to existing files, which have been created with a different edition, and it is not possible to read with a lower edition from files, which have been created with a higher edition.

The following rule applies on principle: if a VPE Document file was created with an Edition A, it can be read without any problems with any higher Edition B. You can not write to an existing file, which was created with a different edition.

If you wish to write with a higher edition to an existing file, which has been created with a lower edition, you need to read the file first as a whole into memory using ReadDoc(). Then delete the file and afterwards write it using WriteDoc(). As an alternative – and to save memory for huge files – you can convert an existing file to the format of a higher edition by opening the existing file as On-Disk file and writing it under a different name to a new file using WriteDoc().