diff --git a/gitlamirator/GitHubLab.py b/gitlamirator/GitHubLab.py
index f5848a37b11982f1c12108bda3e9ce4f8f8dc96e..2ae38277594eb2ea9a7cc2097fc9aa35265b58e3 100755
--- a/gitlamirator/GitHubLab.py
+++ b/gitlamirator/GitHubLab.py
@@ -89,7 +89,7 @@ def record_orphan(entry):
 
 
 def cache_gitlab_group(namespace):
-    """return True when the cache has been updated sucessfully"""
+    """return True when the cache has been updated successfully"""
 
     def get_meta(namespace):
         try:
@@ -155,12 +155,16 @@ def cache_gitlab_group(namespace):
         return do_update(namespace)
 
 
-def add_project_to_gitlab(namespace, repoName, repoUrl, issuesEnabledFor=False):
+def add_project_to_gitlab(namespace, repoNameRaw, repoUrl, issuesEnabledFor=False):
     """
     Add a mirror project to an *existing* group.
 
     The destination namespace should exists beforehand
     """
+    
+    # Before creating a repository in GitLab we need to sanitize the GitHub repository name to make sure it translate into a valid GitLab repository name
+    repoName = sanitize_repo_name_for_gitlab(repoNameRaw)
+    
     logger.debug("invoke add project {}/{} ...".format(namespace, repoName))
 
     # processing only if the cache is populated with the group data
@@ -230,12 +234,19 @@ def add_project_to_gitlab(namespace, repoName, repoUrl, issuesEnabledFor=False):
         logger.error("Can't update group cache for {}".format(namespace))
 
 
+def sanitize_repo_name_for_gitlab(repoName):
+    # Implementation should be improved to cover more scenarios based on https://docs.gitlab.com/ee/user/reserved_names.html
+    return repoName.removeprefix('.')
+
+def sanitize_list_repo_name_for_gitlab(repoNames):
+    return [sanitize_repo_name_for_gitlab(elem) for elem in repoNames]
+
 # print(repos.text)
 def is_valid_source(repo, validRepoTypes):
     """
     Determine if the specified repo has special attributes against input list.
 
-    if the input list validRepoTypes is ommited and any of the special attributes
+    if the input list validRepoTypes is omitted and any of the special attributes
     of ghRepoTypesList is True in the GitHub the repository, then that repo is not considered
     """
     # those are all the possible repo types in GitHub
@@ -273,11 +284,8 @@ def print_github_limits(headers):
 
 
 def prepare_repos(doGetSize=False, **itemSettings):
-    # the dest group is the one read from config if specified otherwise we take
-    # github's namespace
-
-    # the destination GitLab group could be specified by user in YML.
-    # If not, fallback to the github org name
+    # the destination GitLab group could be specified by user in the YAML configuration file.
+    # If not specified in the configuration, fallback to the GitHub organization name
     dstGroup = itemSettings['glDestGroup'] if itemSettings['glDestGroup'] else itemSettings['ghNs']
 
     if itemSettings['ghRepo']:
@@ -322,6 +330,12 @@ def prepare_repos(doGetSize=False, **itemSettings):
 
     else:
         # a whole namespace
+        
+        # If ghRepoOnlyList is defined
+        if itemSettings['ghRepoOnlyList']:
+            # Sanitize the GitHub repository names of the "only" setting as we will compare them with GitLab project names
+            gitlab_repo_only_list = sanitize_list_repo_name_for_gitlab(itemSettings['ghRepoOnlyList'])
+                    
         repos = sessionGihubApi.get(
             "https://api.github.com/users/{}/repos?per_page=100".format(itemSettings['ghNs']), timeout=5)
         if repos.status_code == requests.codes.ok:
@@ -362,11 +376,11 @@ def prepare_repos(doGetSize=False, **itemSettings):
             if cache_gitlab_group(dstGroup):
                 pInGitLab = [p['name'] for p in cacheGroup['projects']]
                 # we sort out if the configured repos are still in GitHub ('only' list)
-                if itemSettings['ghRepoOnlyList']:
-                    if set(itemSettings['ghRepoOnlyList']) <= set(pInGitLab):
-                        logger.info("all configured repos are in Github")
+                if gitlab_repo_only_list:
+                    if set(gitlab_repo_only_list) <= set(pInGitLab):
+                        logger.info("all configured repos are in GitHub")
 
-                    _orphans = set(pInGitLab) - set(itemSettings['ghRepoOnlyList'])
+                    _orphans = set(pInGitLab) - set(gitlab_repo_only_list)
                     if _orphans:
                         logger.warning(
                             'Warning, "ONLY" list:  some of the existing GitLab repos are not specified in the source configuration. See orphan log.')
@@ -377,7 +391,7 @@ def prepare_repos(doGetSize=False, **itemSettings):
                 else:
                     # If the whole org is configured for sync
                     # we print out repos that are in GitLab but not in GitHub (anymore)
-                    _reposNotInGH = list(set(pInGitLab) - set(ghRepos.keys()))
+                    _reposNotInGH = list(set(pInGitLab) - set(sanitize_list_repo_name_for_gitlab(ghRepos.keys())))
                     if _reposNotInGH:
                         _pApiUrls = {p['path_with_namespace']: '{}/projects/{}'.format(config.globalCfg['gitlabApiUrl'], p['id']) for p in cacheGroup['projects']
                                      for orphan in _reposNotInGH if orphan == p['name']}
diff --git a/gitlamirator/mirrorIt.py b/gitlamirator/mirrorIt.py
index 4d9b4581b2e2ac59018ea460b215dc8830740334..2ca424167179ff1bf0a0dc04e7c214396797050f 100755
--- a/gitlamirator/mirrorIt.py
+++ b/gitlamirator/mirrorIt.py
@@ -130,8 +130,8 @@ def gen_settings(item):
             if 'only' in item:
                 logger.error("conflict: can't use 'only' along with specific repository")
                 raise ValueError
-            else:
-                # We have a valid setting. We store the name of the repository in gh_repo and the name of the organization/user in gh_ns
+            else:                
+                #We store the name of the repository in gh_repo and the name of the organization/user in gh_ns
                 gh_ns, gh_repo = src_parts
         # If we don't have a '/' in the ghsrc value, it means that we want to synchronize a whole GitHub organization / all repositories of a user
         elif len(src_parts) == 1:
@@ -159,7 +159,7 @@ def gen_settings(item):
 
     # If we are synchronizing from GitHub
     if src_type == 'ghsrc':
-        # Get the organization / user name and optionnaly (if a specific repository is targeted) the repository name
+        # Get the organization / user name and optionally (if a specific repository is targeted) the repository name
         gh_ns, gh_repo = get_github_parts(item['ghsrc'])
     # If we are synchronizing from something else then GitHub
     else:
diff --git a/tests/test_GitHubLab.py b/tests/test_GitHubLab.py
new file mode 100644
index 0000000000000000000000000000000000000000..863a7396e7369071609081cbab1282c4c80dc147
--- /dev/null
+++ b/tests/test_GitHubLab.py
@@ -0,0 +1,15 @@
+#!/usr/bin/python3
+
+import unittest
+from gitlamirator import GitHubLab
+
+
+class GitHubLabTest(unittest.TestCase):
+    def test_sanitize_gitlab_repo_name(self):
+        valid_gitlab_repo_name = 'my-valid-repo-name'
+        self.assertEqual(GitHubLab.sanitize_repo_name_for_gitlab(valid_gitlab_repo_name), valid_gitlab_repo_name)
+        
+        self.assertEqual(GitHubLab.sanitize_repo_name_for_gitlab('.dot'), 'dot')
+        
+        # TODO uncomment line below once sanitization improved
+        #self.assertEqual(GitHubLab.sanitize_repo_name_for_gitlab('@at'), 'at')
\ No newline at end of file