diff -r cc474cf2c2f5 -r 8e5856182668 dav/main.c
--- a/dav/main.c	Sun Feb 28 13:39:59 2016 +0100
+++ b/dav/main.c	Sun Feb 28 18:14:28 2016 +0100
@@ -574,13 +574,21 @@
     DavResource *res;
     
     int depth = recursive ? -1 : 1;
-    res = dav_query(
-            sn,
-            "select - from %s with depth = %d where lastmodified > %t",
-            path,
-            depth,
-            t);
-      
+    for(int i=0;i<2;i++) {
+        res = dav_query(
+                sn,
+                "select - from %s with depth = %d where lastmodified > %t",
+                path,
+                depth,
+                t);
+        if(!res && sn->error == DAV_UNAUTHORIZED) {
+            if(request_auth(repo, sn)) {
+                continue;
+            }
+        }
+        break;
+    }
+    
     if(!res) {
         print_resource_error(sn, path);
         return -1;
@@ -768,7 +776,17 @@
 }
 
 int put_file(Repository *repo, CmdArgs *a, DavSession *sn, char *path, char *name, FILE *in, off_t len) {
-    DavResource *res = dav_query(sn, "select - from %s", path);
+    DavResource *res = NULL;
+    for(int i=0;i<2;i++) {
+        res = dav_query(sn, "select - from %s", path);
+        if(!res && sn->error == DAV_UNAUTHORIZED) {
+            if(request_auth(repo, sn)) {
+                continue;
+            }
+        }
+        break;
+    }
+    
     if(!res) {
         if(sn->error == DAV_NOT_FOUND) {
             res = dav_resource_new(sn, path);
@@ -817,7 +835,8 @@
     
     char *url = a->argv[0];
     char *path = NULL;
-    DavSession *sn = connect_to_repo(url2repo(url, &path), a);
+    Repository *repo = url2repo(url, &path);
+    DavSession *sn = connect_to_repo(repo, a);
     
     if(set_session_config(sn, a)) {
         return -1;
@@ -829,7 +848,17 @@
         return -1;
     }
     
-    if(dav_delete(res)) {
+    int err = 0;
+    for(int i=0;i<2;i++) {
+        err = dav_delete(res);
+        if(err && sn->error == DAV_UNAUTHORIZED && request_auth(repo, sn)) {
+            continue;
+        } else {
+            break;
+        }
+    }
+    
+    if(err) {
         print_resource_error(sn, res->path);
         fprintf(stderr, "Cannot delete resource.\n");
         return -1;
@@ -848,7 +877,8 @@
     
     char *url = a->argv[0];
     char *path = NULL;
-    DavSession *sn = connect_to_repo(url2repo(url, &path), a);
+    Repository *repo = url2repo(url, &path);
+    DavSession *sn = connect_to_repo(repo, a);
     
     if(set_session_config(sn, a)) {
         return -1;
@@ -874,7 +904,17 @@
     }
     res->iscollection = 1;
     
-    if(dav_create(res)) {
+    int err = 0;
+    for(int i=0;i<2;i++) {
+        err = dav_create(res);
+        if(err && sn->error == DAV_UNAUTHORIZED && request_auth(repo, sn)) {
+            continue;
+        } else {
+            break;
+        }
+    }
+    
+    if(err) {
         print_resource_error(sn, res->path);
         fprintf(stderr, "Cannot create collection.\n");
         return -1;