diff --git a/gui/src/components/uploads/Upload.js b/gui/src/components/uploads/Upload.js
index 7f09f825258597e92e7cec3f45d2a59c780f0f17..e944f0bf4f606f1765939022556e6647b730e4d8 100644
--- a/gui/src/components/uploads/Upload.js
+++ b/gui/src/components/uploads/Upload.js
@@ -354,7 +354,20 @@ class Upload extends React.Component {
 
     const renderRow = (calc, index) => {
       const { mainfile, upload_id, calc_id, parser, tasks, current_task, tasks_status, errors } = calc
-      const color = tasks_status === 'FAILURE' ? 'error' : 'default'
+      let tooltip_html = null
+      let color = tasks_status === 'FAILURE' ? 'error' : 'default'
+      if (tasks_status === 'FAILURE') {
+        tooltip_html = `Calculation processing failed with errors: ${errors.join(', ')}`
+        color = 'error'
+      }
+      if (calc.errors.length > 0) {
+        color = 'error'
+        tooltip_html = `Calculation processed with errors: ${calc.errors.join(', ')}`
+      }
+      if (calc.warnings.length > 0) {
+        color = 'error'
+        tooltip_html = `Calculation processed with warnings: ${calc.warnings.join(', ')}`
+      }
       const processed = tasks_status === 'FAILURE' || tasks_status === 'SUCCESS'
       const row = (
         <TableRow key={index} hover={processed}
@@ -391,10 +404,9 @@ class Upload extends React.Component {
         </TableRow>
       )
 
-      if (tasks_status === 'FAILURE') {
-        const error_html = `Calculation processing failed with errors: ${errors.join(', ')}`
+      if (tooltip_html) {
         return (
-          <Tooltip key={calc_id} title={error_html}>
+          <Tooltip key={calc_id} title={tooltip_html}>
             {row}
           </Tooltip>
         )
diff --git a/nomad/api/raw.py b/nomad/api/raw.py
index 145170dd6b8e9df7b60c83adeced6874be11f305..d7930b72cc1003dad6289d72e34adb6d899c2d50 100644
--- a/nomad/api/raw.py
+++ b/nomad/api/raw.py
@@ -100,7 +100,8 @@ class FileView:
         return self.f.read(size)
 
 
-def get_raw_file_from_upload_path(upload_files, upload_filepath, authorization_predicate):
+def get_raw_file_from_upload_path(
+        upload_files, upload_filepath, authorization_predicate, mainfile: str = None):
     """
     Helper method used by func:`RawFileFromUploadPathResource.get` and
     func:`RawFileFromCalcPathResource.get`.
@@ -148,11 +149,14 @@ def get_raw_file_from_upload_path(upload_files, upload_filepath, authorization_p
         directory_files = upload_files.raw_file_list(upload_filepath)
         if len(directory_files) == 0:
             abort(404, message='There is nothing to be found at %s.' % upload_filepath)
+
+        contents = sorted([dict(name=name, size=size) for name, size in directory_files], key=lambda x: '' if x['name'] == mainfile else x['name'])
+        # if mainfile is not None:
+        #     contents = [mainfile] + [content for content in contents if content['name'] != mainfile]
         return {
             'upload_id': upload_files.upload_id,
             'directory': upload_filepath,
-            'contents': [
-                dict(name=name, size=size) for name, size in directory_files]
+            'contents': contents
         }, 200
 
 
@@ -252,7 +256,9 @@ class RawFileFromCalcPathResource(Resource):
             abort(404, message='The calc with id %s is not part of the upload with id %s.' % (calc_id, upload_id))
 
         upload_filepath = os.path.join(os.path.dirname(calc.mainfile), calc_filepath)
-        return get_raw_file_from_upload_path(upload_files, upload_filepath, authorization_predicate)
+        return get_raw_file_from_upload_path(
+            upload_files, upload_filepath, authorization_predicate,
+            mainfile=os.path.basename(calc.mainfile))
 
 
 @ns.route('/calc/<string:upload_id>/<string:calc_id>/')
diff --git a/nomad/config.py b/nomad/config.py
index 77df549174db014d7b42cff5659b5159ae6f896a..ac13f62664972494645952b0f699dff50e023432 100644
--- a/nomad/config.py
+++ b/nomad/config.py
@@ -176,7 +176,7 @@ commit = gitinfo.commit
 release = 'devel'
 domain = 'DFT'
 service = 'unknown nomad service'
-auxfile_cutoff = 30
+auxfile_cutoff = 100
 console_log_level = logging.WARNING
 
 
diff --git a/nomad/datamodel/base.py b/nomad/datamodel/base.py
index b8f49a77400a02852c1204e3ff285bbdcac7fd42..deae57fecbb3ce995b91f4d23061904855a0002a 100644
--- a/nomad/datamodel/base.py
+++ b/nomad/datamodel/base.py
@@ -85,7 +85,6 @@ class CalcWithMetadata():
         # basic upload and processing related metadata
         self.upload_time: datetime.datetime = None
         self.files: List[str] = None
-        self.file_sizes: List[int] = None
         self.uploader: utils.POPO = None
         self.processed: bool = False
         self.last_processing: datetime.datetime = None
diff --git a/nomad/files.py b/nomad/files.py
index 71e1b2e0a7c043644e434e0ba868e0eaec31ef93..01e250e23f09380ae51a4e660bcd6db83ed9abb6 100644
--- a/nomad/files.py
+++ b/nomad/files.py
@@ -468,9 +468,11 @@ class StagingUploadFiles(UploadFiles):
             if not calc.with_embargo:
                 mainfile = calc.mainfile
                 assert mainfile is not None
-                for filepath in self.calc_files(mainfile):
-                    if not always_restricted(filepath):
-                        public_files[filepath] = None
+                # mainfile might already have been added due to being a auxfile to another calc
+                if mainfile not in public_files:
+                    for filepath in self.calc_files(mainfile, with_cutoff=False):
+                        if not always_restricted(filepath):
+                            public_files[filepath] = None
         # 1.2 remove the non public mainfiles that have been added as auxfiles of public mainfiles
         for calc in upload.calcs:
             if calc.with_embargo:
@@ -542,7 +544,7 @@ class StagingUploadFiles(UploadFiles):
 
         return results
 
-    def calc_files(self, mainfile: str, with_mainfile: bool = True) -> Iterable[str]:
+    def calc_files(self, mainfile: str, with_mainfile: bool = True, with_cutoff: bool = True) -> Iterable[str]:
         """
         Returns all the auxfiles and mainfile for a given mainfile. This implements
         nomad's logic about what is part of a calculation and what not. The mainfile
@@ -559,16 +561,21 @@ class StagingUploadFiles(UploadFiles):
         calc_dir = os.path.dirname(mainfile_object.os_path)
         calc_relative_dir = calc_dir[len(self._raw_dir.os_path) + 1:]
 
-        ls = os.listdir(calc_dir)
-        if len(ls) > config.auxfile_cutoff:
-            # If there are two many of them, its probably just a directory with lots of
-            # calculations. In this case it does not make any sense to provide thousands of
-            # aux files.
-            return [mainfile] if with_mainfile else []
+        file_count = 0
+        aux_files: List[str] = []
+        for filename in os.listdir(calc_dir):
+            if filename != mainfile_basename and os.path.isfile(os.path.join(calc_dir, filename)):
+                aux_files.append(os.path.join(calc_relative_dir, filename))
+                file_count += 1
+
+            if with_cutoff and file_count > config.auxfile_cutoff:
+                # If there are two many of them, its probably just a directory with lots of
+                # calculations. In this case it does not make any sense to provide thousands of
+                # aux files.
+                break
+
+        aux_files = sorted(aux_files)
 
-        aux_files = sorted(
-            os.path.join(calc_relative_dir, path) for path in ls
-            if os.path.isfile(os.path.join(calc_dir, path)) and path != mainfile_basename)
         if with_mainfile:
             return [mainfile] + aux_files
         else:
diff --git a/nomad/processing/data.py b/nomad/processing/data.py
index d54cd60763aa080ccde125c0dae870d0434fd616..53ae8f660e099979c6702c88b901dc556cf5080f 100644
--- a/nomad/processing/data.py
+++ b/nomad/processing/data.py
@@ -164,9 +164,13 @@ class Calc(Proc):
             calc_with_metadata.nomad_commit = config.commit
             calc_with_metadata.last_processing = datetime.now()
             calc_with_metadata.files = self.upload_files.calc_files(self.mainfile)
-            self.preprocess_files(calc_with_metadata.files)
             self.metadata = calc_with_metadata.to_dict()
 
+            if len(calc_with_metadata.files) >= config.auxfile_cutoff:
+                self.warning(
+                    'This calc has many aux files in its directory. '
+                    'Have you placed many calculations in the same directory?')
+
             self.parsing()
             self.normalizing()
             self.archiving()
@@ -215,36 +219,6 @@ class Calc(Proc):
             self.upload.reload()
             self.upload.check_join()
 
-    def preprocess_files(self, filepaths):
-        for path in filepaths:
-            if os.path.basename(path) == 'POTCAR':
-                # create checksum
-                hash = hashlib.sha224()
-                with open(self.upload_files.raw_file_object(path).os_path, 'rb') as f:
-                    for line in f.readlines():
-                        hash.update(line)
-
-                checksum = hash.hexdigest()
-
-                # created stripped POTCAR
-                stripped_path = path + '.stripped'
-                with open(self.upload_files.raw_file_object(stripped_path).os_path, 'wt') as f:
-                    f.write('Stripped POTCAR file. Checksum of original file (sha224): %s\n' % checksum)
-                os.system(
-                    '''
-                        awk < %s >> %s '
-                        BEGIN { dump=1 }
-                        /End of Dataset/ { dump=1 }
-                        dump==1 { print }
-                        /END of PSCTR/ { dump=0 }'
-                    ''' % (
-                        self.upload_files.raw_file_object(path).os_path,
-                        self.upload_files.raw_file_object(stripped_path).os_path))
-
-                filepaths.append(stripped_path)
-
-        return filepaths
-
     @task
     def parsing(self):
         context = dict(parser=self.parser, step=self.parser)
@@ -652,6 +626,35 @@ class Upload(Proc):
             self.fail('bad .zip/.tar file', log_level=logging.INFO)
             return
 
+    def _preprocess_files(self, path):
+        """
+        Some files need preprocessing. Currently we need to add a stripped POTCAR version
+        and always restrict/embargo the original.
+        """
+        if os.path.basename(path) == 'POTCAR':
+            # create checksum
+            hash = hashlib.sha224()
+            with open(self.staging_upload_files.raw_file_object(path).os_path, 'rb') as orig_f:
+                for line in orig_f.readlines():
+                    hash.update(line)
+
+            checksum = hash.hexdigest()
+
+            # created stripped POTCAR
+            stripped_path = path + '.stripped'
+            with open(self.staging_upload_files.raw_file_object(stripped_path).os_path, 'wt') as stripped_f:
+                stripped_f.write('Stripped POTCAR file. Checksum of original file (sha224): %s\n' % checksum)
+            os.system(
+                '''
+                    awk < %s >> %s '
+                    BEGIN { dump=1 }
+                    /End of Dataset/ { dump=1 }
+                    dump==1 { print }
+                    /END of PSCTR/ { dump=0 }'
+                ''' % (
+                    self.staging_upload_files.raw_file_object(path).os_path,
+                    self.staging_upload_files.raw_file_object(stripped_path).os_path))
+
     def match_mainfiles(self) -> Generator[Tuple[str, object], None, None]:
         """
         Generator function that matches all files in the upload to all parsers to
@@ -663,6 +666,7 @@ class Upload(Proc):
         directories_with_match: Dict[str, str] = dict()
         upload_files = self.staging_upload_files
         for filename in upload_files.raw_file_manifest():
+            self._preprocess_files(filename)
             try:
                 parser = match_parser(filename, upload_files)
                 if parser is not None:
diff --git a/tests/data/proc/examples_large_dir.zip b/tests/data/proc/examples_large_dir.zip
new file mode 100644
index 0000000000000000000000000000000000000000..dbf3663359d8e8ec414bcf434d776ae5d8b43fd2
Binary files /dev/null and b/tests/data/proc/examples_large_dir.zip differ
diff --git a/tests/processing/test_data.py b/tests/processing/test_data.py
index e56455c6d10848459d2a006b6a8a8d1b80749d3b..eb2e415027d7d07b2e12a4e5a1a02525dd091644 100644
--- a/tests/processing/test_data.py
+++ b/tests/processing/test_data.py
@@ -109,6 +109,14 @@ def test_processing(processed, no_warn, mails, monkeypatch):
     assert re.search(r'Processing completed', mails.messages[0].data.decode('utf-8')) is not None
 
 
+def test_processing_with_large_dir(test_user, proc_infra):
+    upload_path = 'tests/data/proc/examples_large_dir.zip'
+    upload_id = upload_path[:-4]
+    upload = run_processing((upload_id, upload_path), test_user)
+    for calc in upload.calcs:
+        assert len(calc.warnings) == 1
+
+
 def test_publish(non_empty_processed: Upload, no_warn, example_user_metadata, with_publish_to_coe_repo, monkeypatch):
     processed = non_empty_processed
     processed.compress_and_set_metadata(example_user_metadata)
diff --git a/tests/test_api.py b/tests/test_api.py
index acc8a947ac4e4da5b3c855babead6096823b3665..67ba51f68cafdea1983d1ba8968328d4e92eeae3 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -460,6 +460,7 @@ class TestUploads:
     #     assert rv.status_code == 400
 
     def test_potcar(self, client, proc_infra, test_user_auth):
+        # only the owner, shared with people are supposed to download the original potcar file
         example_file = 'tests/data/proc/examples_potcar.zip'
         rv = client.put('/uploads/?local_path=%s' % example_file, headers=test_user_auth)