Hi,
providing different fonts for the pdf files requires to install font files with the visForms installation. These font files are really big and made the visForms installation file a very big file. Therefore I decided to not include the PDF font files directly into the installation zip file, but during the installation/update of visForms there runs some code, that should stream the font files from our server and install the files on your web server.
I think, that this process was not successfull for an unknown reason on your website and now the font files are missing.
You can check. If you do not have a file "helvetica.php" in the folder media\com_visforms\tcpdf\fonts then installing the pdf fonts was not successful.
If so, please try the following:
1. Download :
vi-solutions.de/images/pdfs/pdffonts.zip
2. Unzip the downloaded file
3. copy the content of the folder "fonts" inside the extracted folder into the folder media\com_visforms\tcpdf\fonts on your server.
Regards,
Aicha