diff --git a/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageDB.pm b/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageDB.pm
index 4d73a97f985..73b7727dbaa 100644
--- a/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageDB.pm
+++ b/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageDB.pm
@@ -201,7 +201,8 @@ sub ArticleWriteAttachment {
     my $NewFileName = $Param{Filename};
     my %UsedFile;
     my %Index = $Self->ArticleAttachmentIndex(
-        ArticleID => $Param{ArticleID},
+        ArticleID     => $Param{ArticleID},
+        OnlyMyBackend => 1,
     );
 
     for my $IndexFile ( sort keys %Index ) {
diff --git a/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageFS.pm b/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageFS.pm
index d3cff2f6fc3..da9f3cb6376 100644
--- a/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageFS.pm
+++ b/Kernel/System/Ticket/Article/Backend/MIMEBase/ArticleStorageFS.pm
@@ -323,7 +323,8 @@ sub ArticleWriteAttachment {
     my $NewFileName = $Param{Filename};
     my %UsedFile;
     my %Index = $Self->ArticleAttachmentIndex(
-        ArticleID => $Param{ArticleID},
+        ArticleID     => $Param{ArticleID},
+        OnlyMyBackend => 1,
     );
 
     # Normalize filenames to find file names which are identical but in a different unicode form.