diff --git a/v2.5/generators/nlojet++/interface/check/compare-table-helper.py b/v2.5/generators/nlojet++/interface/check/compare-table-helper.py
index 095ab0ddefc2caf2e42609b0515772fecd9a906b..0f40493ba7fb696c7f9f58ab0752c3d68a436cde 100755
--- a/v2.5/generators/nlojet++/interface/check/compare-table-helper.py
+++ b/v2.5/generators/nlojet++/interface/check/compare-table-helper.py
@@ -3,7 +3,11 @@
 import os
 import sys
 
-import fastnlo as fnlo
+try:
+    import fastnlo as fnlo
+except ModuleNotFoundError:
+    print("compare-table-helper: fastNLO Python extension not found")
+    sys.exit(77)
 
 LIBDIR = os.environ["LIBDIR"]
 
diff --git a/v2.5/generators/nlojet++/interface/check/fnlo-compare-tables.py b/v2.5/generators/nlojet++/interface/check/fnlo-compare-tables.py
index 3a17694a3c38ccb4e9d373c4180103f949dae79c..7d2e6ba87bd0675d4c7d6f911540d0955532a28b 100755
--- a/v2.5/generators/nlojet++/interface/check/fnlo-compare-tables.py
+++ b/v2.5/generators/nlojet++/interface/check/fnlo-compare-tables.py
@@ -1,8 +1,13 @@
 #!/usr/bin/env python3
 
+import sys
 import os
 
-import fastnlo as fnlo
+try:
+    import fastnlo as fnlo
+except ModuleNotFoundError:
+    print("fastNLO Python extension not found")
+    sys.exit(77)
 
 LIBDIR = os.environ["LIBDIR"]
 
diff --git a/v2.5/generators/nlojet++/interface/check/fnlo-nj-lotest.pl.in b/v2.5/generators/nlojet++/interface/check/fnlo-nj-lotest.pl.in
index 98119c888117bc8d2657e9240cea521050070d1e..105bbc19f64259875599a9b0dd798f53726e68c0 100755
--- a/v2.5/generators/nlojet++/interface/check/fnlo-nj-lotest.pl.in
+++ b/v2.5/generators/nlojet++/interface/check/fnlo-nj-lotest.pl.in
@@ -72,6 +72,10 @@ if ( $ret ) {die "fnlo-tk-nlotest: Ungzipping test table ${tabgz} failed: $ret,
 $cmd = "./compare-table-helper.py ./${tabl} output/${tabl} > lodiff.log";
 print "Executing command: $cmd\n";
 $ret = system("$cmd");
+if ( $ret == 77 ) {
+    print "fnlo-nj-lotest: Skipping LO production unit test.";
+    exit 77;
+}
 if ( $ret ) {die "fnlo-nj-lotest: LO table production unit test failed, results are different!\n";}
 
 print "fnlo-nj-lotest: LO table production unit test passed.\n";
diff --git a/v2.5/generators/nlojet++/interface/check/fnlo-nj-nlotest.pl.in b/v2.5/generators/nlojet++/interface/check/fnlo-nj-nlotest.pl.in
index 3d6a1304c2d8fd8047497f5fc3b2119ce8051152..2018db4294474ee7420726c7e2a00aaa51a568ce 100755
--- a/v2.5/generators/nlojet++/interface/check/fnlo-nj-nlotest.pl.in
+++ b/v2.5/generators/nlojet++/interface/check/fnlo-nj-nlotest.pl.in
@@ -72,6 +72,10 @@ if ( $ret ) {die "fnlo-tk-nlotest: Ungzipping test table ${tabgz} failed: $ret,
 $cmd = "./compare-table-helper.py ./${tabn} output/${tabn} > lodiff.log";
 print "Executing command: $cmd\n";
 $ret = system("$cmd");
+if ( $ret == 77 ) {
+    print "fnlo-nj-lotest: Skipping LO production unit test.";
+    exit 77;
+}
 if ( $ret ) {die "fnlo-nj-lotest: NLO table production unit test failed, results are different!\n";}
 
 print "fnlo-nj-nlotest: NLO table production unit test passed.\n";