diff --git a/installers/common.sh b/installers/common.sh
index e8818cd..424155f 100755
--- a/installers/common.sh
+++ b/installers/common.sh
@@ -385,7 +385,7 @@ function optimize_php() {
 }
 
 function build_R1 () {
-  if [-f /boot/armbianEnv.txt]; then
+  if [ -f /boot/armbianEnv.txt]; then
     sudo sed -i "1i extraargs=net.ifnames=0" /boot/armbianEnv.txt
   fi
 }