diff --git a/cadc-access-control-server/build.gradle b/cadc-access-control-server/build.gradle
index c8bc364c..1fa08618 100644
--- a/cadc-access-control-server/build.gradle
+++ b/cadc-access-control-server/build.gradle
@@ -13,7 +13,7 @@ sourceCompatibility = 1.8
 
 group = 'org.opencadc'
 
-version = '1.3.33'
+version = '1.3.35'
 
 description = 'OpenCADC User+Group server library'
 def git_url = 'https://github.com/opencadc/ac'
diff --git a/cadc-access-control-server/src/main/java/ca/nrc/cadc/ac/server/ldap/LdapGroupDAO.java b/cadc-access-control-server/src/main/java/ca/nrc/cadc/ac/server/ldap/LdapGroupDAO.java
index 0d303630..9dbdc53e 100755
--- a/cadc-access-control-server/src/main/java/ca/nrc/cadc/ac/server/ldap/LdapGroupDAO.java
+++ b/cadc-access-control-server/src/main/java/ca/nrc/cadc/ac/server/ldap/LdapGroupDAO.java
@@ -3,7 +3,7 @@
  *******************  CANADIAN ASTRONOMY DATA CENTRE  *******************
  **************  CENTRE CANADIEN DE DONNÉES ASTRONOMIQUES  **************
  *
- *  (c) 2019.                            (c) 2019.
+ *  (c) 2023.                            (c) 2023.
  *  Government of Canada                 Gouvernement du Canada
  *  National Research Council            Conseil national de recherches
  *  Ottawa, Canada, K1A 0R6              Ottawa, Canada, K1A 0R6
@@ -473,8 +473,12 @@ public void searchEntryReturned(SearchResultEntry sre)
                             String gname = sre.getAttributeValue(LDAP_CN);
                             String gidstr = sre.getAttributeValue(LDAP_GID_NUMBER);
                             Integer gid = Integer.valueOf(gidstr);
-                            PosixGroup pg = new PosixGroup(gid, new GroupURI(gmsResourceID, gname));
-                            ret.add(pg);
+                            try {
+                                PosixGroup pg = new PosixGroup(gid, new GroupURI(gmsResourceID, gname));
+                                ret.add(pg);
+                            } catch (IllegalArgumentException ex) {
+                                logger.warn("invalid group name: " + gname + " -- SKIP");
+                            }
                             
                             long t2 = System.currentTimeMillis();
                             long dt = t2 - t1;