diff --git a/run-document-server.sh b/run-document-server.sh
index 5cd2abc..61e7296 100755
--- a/run-document-server.sh
+++ b/run-document-server.sh
@@ -39,7 +39,7 @@ fi
 
 SSL_CERTIFICATES_DIR="/usr/share/ca-certificates/ds"
 mkdir -p ${SSL_CERTIFICATES_DIR}
-if [[ -d $DATA_DIR/certs ]] && [ "$(ls -A $DATA_DIR/certs)" ]; then
+if [[ -d $DATA_DIR/certs ]] && [[ "$(ls -A $DATA_DIR/certs)" ]]; then
     cp -f ${DATA_DIR}/certs/* ${SSL_CERTIFICATES_DIR}
     chmod 644 ${SSL_CERTIFICATES_DIR}/*.crt ${SSL_CERTIFICATES_DIR}/*.pem
     chmod 400 ${SSL_CERTIFICATES_DIR}/*.key