diff --git a/updater/install.c b/updater/install.c
index ad89556..aa80d75 100644
--- a/updater/install.c
+++ b/updater/install.c
@@ -86,6 +86,8 @@ char* MountFn(const char* name, State* state, int argc, Expr* argv[]) {
     } else {
         if (mount(location, mount_point, type,
                   MS_NOATIME | MS_NODEV | MS_NODIRATIME, "") < 0) {
+            fprintf(stderr, "%s: failed to mount %s at %s: %s\n",
+                    name, location, mount_point, strerror(errno));
             result = strdup("");
         } else {
             result = mount_point;
@@ -348,6 +350,7 @@ char* PackageExtractFileFn(const char* name, State* state,
 
 
 // symlink target src1 src2 ...
+//    unlinks any previously existing src1, src2, etc before creating symlinks.
 char* SymlinkFn(const char* name, State* state, int argc, Expr* argv[]) {
     if (argc == 0) {
         return ErrorAbort(state, "%s() expects 1+ args, got %d", name, argc);
@@ -364,7 +367,16 @@ char* SymlinkFn(const char* name, State* state, int argc, Expr* argv[]) {
 
     int i;
     for (i = 0; i < argc-1; ++i) {
-        symlink(target, srcs[i]);
+        if (unlink(srcs[i]) < 0) {
+            if (errno != ENOENT) {
+                fprintf(stderr, "%s: failed to remove %s: %s\n",
+                        name, srcs[i], strerror(errno));
+            }
+        }
+        if (symlink(target, srcs[i]) < 0) {
+            fprintf(stderr, "%s: failed to symlink %s to %s: %s\n",
+                    name, srcs[i], target, strerror(errno));
+        }
         free(srcs[i]);
     }
     free(srcs);
@@ -424,8 +436,14 @@ char* SetPermFn(const char* name, State* state, int argc, Expr* argv[]) {
         }
 
         for (i = 3; i < argc; ++i) {
-            chown(args[i], uid, gid);
-            chmod(args[i], mode);
+            if (chown(args[i], uid, gid) < 0) {
+                fprintf(stderr, "%s: chown of %s to %d %d failed: %s\n",
+                        name, args[i], uid, gid, strerror(errno));
+            }
+            if (chmod(args[i], mode) < 0) {
+                fprintf(stderr, "%s: chmod of %s to %o failed: %s\n",
+                        name, args[i], mode, strerror(errno));
+            }
         }
     }
     result = strdup("");