diff --git a/htdocs/core/modules/commande/doc/pdf_einstein.modules.php b/htdocs/core/modules/commande/doc/pdf_einstein.modules.php
index 3bc5575189f..1182972f0bd 100644
--- a/htdocs/core/modules/commande/doc/pdf_einstein.modules.php
+++ b/htdocs/core/modules/commande/doc/pdf_einstein.modules.php
@@ -257,11 +257,13 @@ class pdf_einstein extends ModelePDFCommandes
 				$file = $dir."/SPECIMEN.pdf";
 			} else {
 				// Possibility to use suffix for proforma
+				$suffix = '';
 				if (!empty($conf->global->PROFORMA_PDF_WITH_SUFFIX)) {
 					$suffix = (GETPOST('model', 2)=='proforma') ? $conf->global->PROFORMA_PDF_WITH_SUFFIX : '';
 				}
 
 				$objectref = dol_sanitizeFileName($object->ref);
+				$suffix = dol_sanitizeFileName($suffix);
 				$dir = $conf->commande->multidir_output[$object->entity]."/".$objectref;
 				$file = $dir . "/" .$objectref.$suffix.".pdf";
 			}