diff --git a/sirepo/package_data/static/js/sirepo-components.js b/sirepo/package_data/static/js/sirepo-components.js
index f383f1fa91..f34d237374 100644
--- a/sirepo/package_data/static/js/sirepo-components.js
+++ b/sirepo/package_data/static/js/sirepo-components.js
@@ -4687,11 +4687,8 @@ SIREPO.app.service('fileUpload', function(authState, msgRouter, errorService) {
                 fd.append(k, args[k]);
             }
         }
-        srdbg('authState', authState);
-        srdbg('file', file);
-        srdbg('file size = ', file.size);
         if (file.size > authState.max_message_bytes) {
-            callback({error: 'File was too large for upload'});
+            callback({error: `File of size=${file.size} bytes was too large for upload. Max size=${authState.max_message_bytes} bytes`});
             return;
         }
         //TODO(robnagler) formData needs to be handled properly
@@ -4701,11 +4698,14 @@ SIREPO.app.service('fileUpload', function(authState, msgRouter, errorService) {
         }).then(
             function(response) {
                 srdbg('onSuccess response:', response);
+                if (response.data.status == 500) {
+                    callback({error: 'File upload failed due to server error'});
+                    return;
+                }
                 callback(response.data);
             },
             function(response) {
-                srdbg('onRejected response:', response);
-                callback({error: 'File Upload Failed'});
+                callback({error: 'File Upload Failed (reason unknown)'});
             },
         );
     };
diff --git a/sirepo/reply.py b/sirepo/reply.py
index 92bfb92f8a..b38a39baef 100644
--- a/sirepo/reply.py
+++ b/sirepo/reply.py
@@ -471,8 +471,11 @@ def _content():
                     x = pkcompat.from_bytes(x)
                 return x, k
             elif isinstance(c, _Base):
-                return c.websocket_content()
+                res = c.websocket_content()
+                pkdp("\n\n\n INSTANCE HIT res={}", res)
+                return res
             else:
+                pkdp("\n\n\n NON INSTANCE HIT. c={} k={}", c, k)
                 return c, k
 
         async def _send(content, kind):
@@ -584,6 +587,7 @@ def _gen_exception_reply_SReplyExc(self, args):
         return self.from_kwargs(**r.__attrs)
 
     def _gen_exception_reply_ServerError(self, args):
+        pkdp("\n\n\nreply_serverError hit, args={}", args)
         return self._gen_http_exception(500)
 
     def _gen_exception_reply_SPathNotFound(self, args):
@@ -591,6 +595,7 @@ def _gen_exception_reply_SPathNotFound(self, args):
         return self._gen_http_exception(404)
 
     def _gen_exception_reply_SRException(self, args):
+        pkdp("\n\n\nHIT FOR GEN reply_SRException")
         if args.get("params") is None:
             args.params = PKDict()
         args.pksetdefault(sim_type=lambda: self.qcall.sim_type_uget())
@@ -610,13 +615,12 @@ def _gen_exception_reply_WWWAuthenticate(self, args):
             401, headers=PKDict({"WWW-Authenticate": 'Basic realm="*"'})
         )
 
-    # def _gen_http_exception(self, code, headers=None):
-    #     return self.from_kwargs(
-    #         content=_HTTPException(PKDict(code=code, headers=headers))
-    #     )
     def _gen_http_exception(self, status, headers=None):
+        pkdp("\n\n\n\nHIT, status={} headers={} \n\n\n\n", status, headers)
         return self.from_kwargs(
-            content=_HTTPException(PKDict(status=status, code=status, headers=headers))
+            # TODO (gurhar1133): figure out why _HTTPException doesn't work
+            # but _Object does
+            content=_Object(PKDict(status=status, code=status, headers=headers))
         )
 
     def _gen_redirect_for_anchor(self, uri, **kwargs):
@@ -704,10 +708,12 @@ def _sr_exception(self, routeName, params, **kwargs):
         # certain cases.
         # TODO(robnagler) this probably should be an assert
         params.pkdel("simulationType")
-        return (
+        res = (
             PKDict(routeName=routeName, params=params),
             sirepo.const.SCHEMA_COMMON.websocketMsg.kind.srException,
         )
+        pkdp("\n\n\n res in _sr_exception = {}", res)
+        return res
 
     def _value(self, value=None):
         return (
@@ -734,12 +740,15 @@ def websocket_content(self):
 
 class _HTTPException(_Base):
     def http_response(self, sreply):
+        pkdp("\n\n\n hit for http_response")
         if self.value.headers:
             for k, v in self.value.headers.items():
                 sreply.header_set(k, v)
         return self._http_error(self.value.code, sreply)
 
     def websocket_content(self):
+        pkdp("\n\n\n hit for websocket_content() \n\n")
+        pkdp("\n\n\n self.value.code={}", self.value.code)
         return self._sr_exception(
             routeName="httpException", params=PKDict(code=self.value.code)
         )
@@ -808,4 +817,5 @@ def _sim_type():
         )
 
     def websocket_content(self):
+        pkdp("\n\n\n websocket_content self.value={}", self.value)
         return self._sr_exception(**self.value)
diff --git a/sirepo/server.py b/sirepo/server.py
index bb1cdc7cf1..adcdf764f5 100644
--- a/sirepo/server.py
+++ b/sirepo/server.py
@@ -591,6 +591,7 @@ async def api_updateFolder(self):
     )
     async def api_uploadFile(self, simulation_type, simulation_id, file_type):
         # assert 0, "ASSERTION TEST"
+        # raise sirepo.util.UserAlert("TEST USER ALERT")
         f = self.sreq.form_file_get()
         req = self.parse_params(
             file_type=file_type,