diff --git a/default.conf b/default.conf
index 109880f..5f163df 100644
--- a/default.conf
+++ b/default.conf
@@ -29,6 +29,13 @@ server {
   rewrite ^/.well-known/carddav /remote.php/carddav/ permanent;
   rewrite ^/.well-known/caldav /remote.php/caldav/ permanent;
 
+  # Support Let's Encrypt TLS cert validation
+  location /.well-known/acme-challenge {
+    allow all;
+    log_not_found off;
+    access_log off;
+  }
+
   location = /robots.txt {
     allow all;
     log_not_found off;
@@ -80,4 +87,4 @@ server {
   location ~* \.(?:jpg|jpeg|gif|bmp|ico|png|swf)$ {
     access_log off;
   }
-}
\ No newline at end of file
+}