diff --git a/edx_proctoring/backends/software_secure.py b/edx_proctoring/backends/software_secure.py
index e3b4d96ee35..1070a864b74 100644
--- a/edx_proctoring/backends/software_secure.py
+++ b/edx_proctoring/backends/software_secure.py
@@ -38,7 +38,7 @@
 log = logging.getLogger(__name__)
 
 
-SOFTWARE_SECURE_INVALID_CHARS = '[]<>#:|?/\'"*\\'
+SOFTWARE_SECURE_INVALID_CHARS = '[]<>#:|!?/\'"*\\'
 
 
 class SoftwareSecureBackendProvider(ProctoringBackendProvider):