diff --git a/include/main.h b/include/main.h
index 129493d..d6303e4 100644
--- a/include/main.h
+++ b/include/main.h
@@ -7,7 +7,8 @@ enum ResultCode {
   RC_OK = 0,                  // No problem (so far)
   RC_EXISTS = 1,              // On upload, the file to be uploaded already existed
   RC_OPEN_FAILED = 2,         // On upload, opening the file for writing failed
-  RC_WRONG_TARGET = 3         // On upload, the given URL was not a directory
+  RC_WRONG_TARGET = 3,        // On upload, the given URL was not a directory
+  RC_WRITE_FAILED = 4         // On upload, a write operation to the file failed
 };
 
 enum RequestType {
@@ -23,6 +24,7 @@ struct ConnectionState {
   uint8_t uploadRequest;
 
   FILE *upload_fd;
+  char uploadFilename[PATH_MAX];
 
   enum ResultCode result;
   enum RequestType requestType;
diff --git a/src/main.c b/src/main.c
index 670b9b8..c8ab643 100644
--- a/src/main.c
+++ b/src/main.c
@@ -231,7 +231,7 @@ int serv_result_page(struct MHD_Connection *connection, struct ConnectionState *
   int ret;
 
   char *message, *title;
-  unsigned int resultCode;
+  unsigned int resultCode = MHD_HTTP_OK;
 
   switch(connstate->result) {
     case RC_OK:
@@ -257,6 +257,12 @@ int serv_result_page(struct MHD_Connection *connection, struct ConnectionState *
       title = "Target error";
       resultCode = MHD_HTTP_INTERNAL_SERVER_ERROR;
       break;
+
+    case RC_WRITE_FAILED:
+      message = "A write error occurred while storing uploaded data to the file.";
+      title = "Write error";
+      resultCode = MHD_HTTP_INTERNAL_SERVER_ERROR;
+      break;
   }
 
   char *buffer = malloc(strlen(HEADER1 HEADER2 FOOTER) + 1024);
@@ -299,40 +305,50 @@ static int post_processor(void *cls,
     if(strcmp("data", key) == 0) {
       if(ci->upload_fd == NULL) {
         // file pointer not allocated yet
-        // determine the path where to store the uploaded file
-        char uploadFilename[PATH_MAX];
 
+        // check if we are storing the new file into a directory
         if(!S_ISDIR(ci->targetStat.st_mode)) {
           LOG(LVL_WARN, "Cannot upload %s: Target path is not an existing directory.", filename);
           ci->result = RC_WRONG_TARGET;
           return MHD_NO;
         }
 
-        strncpy(uploadFilename, ci->localFileName, PATH_MAX);
-        strncat(uploadFilename, "/", PATH_MAX);
-        strncat(uploadFilename, filename, PATH_MAX);
+        // determine the path where to store the uploaded file
+        strncpy(ci->uploadFilename, ci->localFileName, PATH_MAX);
+        strcat(ci->uploadFilename, "/");
+        strncat(ci->uploadFilename, filename, PATH_MAX-strlen(ci->uploadFilename));
 
         // check if the file already exists
-        FILE *tmp = fopen(uploadFilename, "rb");
+        FILE *tmp = fopen(ci->uploadFilename, "rb");
         if(tmp) {
-          LOG(LVL_WARN, "Cannot upload to %s: file exists.", uploadFilename);
+          LOG(LVL_WARN, "Cannot upload to %s: file exists.", ci->uploadFilename);
           ci->result = RC_EXISTS;
           fclose(tmp);
           return MHD_NO;
         }
 
         // file does not exist and can therefore be opened for writing
-        ci->upload_fd = fopen(uploadFilename, "wb");
+        ci->upload_fd = fopen(ci->uploadFilename, "wb");
         if(!ci->upload_fd) {
-          LOG(LVL_WARN, "Cannot upload to %s: file cannot be created.", uploadFilename);
+          LOG(LVL_WARN, "Cannot upload to %s: file cannot be created.", ci->uploadFilename);
           ci->result = RC_OPEN_FAILED;
           return MHD_NO;
         }
 
-        fwrite(data, size, 1, ci->upload_fd);
+        if(0 == fwrite(data, size, 1, ci->upload_fd)) {
+          LOG(LVL_WARN, "Cannot upload to %s: write operation failed.", ci->uploadFilename);
+          ci->result = RC_WRITE_FAILED;
+          return MHD_NO;
+        }
+
+        LOG(LVL_WARN, "Upload to %s started successfully.", ci->uploadFilename);
       } else {
         // file descriptor is already open
-        fwrite(data, size, 1, ci->upload_fd);
+        if(0 == fwrite(data, size, 1, ci->upload_fd)) {
+          LOG(LVL_WARN, "Cannot upload to %s: write operation failed.", ci->uploadFilename);
+          ci->result = RC_WRITE_FAILED;
+          return MHD_NO;
+        }
       }
     }
     return MHD_YES;