diff --git a/run-document-server.sh b/run-document-server.sh
index 99f6ddc..759a59c 100755
--- a/run-document-server.sh
+++ b/run-document-server.sh
@@ -39,16 +39,16 @@ fi
 
 SSL_CERTIFICATES_DIR="/usr/share/ca-certificates/ds"
 mkdir -p ${SSL_CERTIFICATES_DIR}
-if [[ -d $DATA_DIR/certs ]]; then
-   if [[ "$(ls -A $DATA_DIR/certs | grep .crt )" ]]; then
+if [[ -d ${DATA_DIR}/certs ]]; then
+   if [ -e ${DATA_DIR}/certs/*.crt ]; then
      cp -f ${DATA_DIR}/certs/*.crt ${SSL_CERTIFICATES_DIR}
      chmod 644 ${SSL_CERTIFICATES_DIR}/*.crt
    fi
-   if [[ "$(ls -A $DATA_DIR/certs | grep .pem )" ]]; then
+   if [ -e ${DATA_DIR}/certs/*.pem ]; then
      cp -f ${DATA_DIR}/certs/*.pem ${SSL_CERTIFICATES_DIR}
      chmod 644 ${SSL_CERTIFICATES_DIR}/*.pem
    fi
-   if [[ "$(ls -A $DATA_DIR/certs | grep .key )" ]]; then
+   if [ -e ${DATA_DIR}/certs/*.key ]; then
      cp -f ${DATA_DIR}/certs/*.key ${SSL_CERTIFICATES_DIR}
      chmod 400 ${SSL_CERTIFICATES_DIR}/*.key
    fi