diff --git a/src/nopayloadclient.cpp b/src/nopayloadclient.cpp
index 03bc6ae..3adbef4 100644
--- a/src/nopayloadclient.cpp
+++ b/src/nopayloadclient.cpp
@@ -262,12 +262,14 @@ json NoPayloadClient::makeResp(T msg) {
     return {{"code", 0}, {"msg", msg}};
 }
 
+template json NoPayloadClient::makeResp(json);
+
 // Private
 void NoPayloadClient::insertPayload(Payload &pl, IOV &iov) {
     prepareInsertIov(pl);
     pl_handler_.prepareUploadFile(pl);
-    insertIov(pl, iov);
     pl_handler_.uploadFile(pl);
+    insertIov(pl, iov);
 }
 
 void NoPayloadClient::prepareInsertIov(Payload &pl) {
diff --git a/src/plhandler.cpp b/src/plhandler.cpp
index 9902e96..4576e35 100644
--- a/src/plhandler.cpp
+++ b/src/plhandler.cpp
@@ -73,7 +73,12 @@ void PLHandler::checkRemoteDirExists() {
 
 void PLHandler::createDirectory(const string& path){
     if (!fs::is_directory(path) || !fs::exists(path)) {
-        fs::create_directories(path);
+      try{
+          fs::create_directories(path);
+      }
+      catch(...){
+        throw BaseException("remote payload directory "+path+" could not be created");
+      }
     }
 }
 
@@ -85,7 +90,10 @@ void PLHandler::prepareUploadFile(const Payload& pl) {
 
 void PLHandler::copyFile(const string& local_url, const string& remote_url) {
     if (!fs::exists(remote_url)) {
-        fs::copy_file(local_url, remote_url);
+      if (! fs::copy_file(local_url, remote_url))
+      {
+        throw BaseException("could not copy "+local_url+" to "+remote_url);
+      }
     }
 }
 
diff --git a/src/realwrapper.cpp b/src/realwrapper.cpp
index 5eea53d..d4948f7 100644
--- a/src/realwrapper.cpp
+++ b/src/realwrapper.cpp
@@ -1,6 +1,7 @@
 #include <nopayloadclient/realwrapper.hpp>
 
 #include <cstdlib>
+#include <random>
 
 namespace nopayloadclient {
 
@@ -13,8 +14,9 @@ RealWrapper::RealWrapper(const json& config) {
 }
 
 void RealWrapper::sleep(int retry_number) {
-    srand(time(0));
-    int n_sleep = rand()%(retry_sleep_mean_*2)+1; // add random sleep
+    std::random_device rd;
+    std::uniform_int_distribution<int> dist(1, retry_sleep_mean_*2);
+    int n_sleep = dist(rd); // add random sleep
     logging::debug("sleeping for " + std::to_string(n_sleep) + " seconds before retrying...");
     std::this_thread::sleep_for(std::chrono::seconds(n_sleep));
 }