diff --git a/compiler2/titanver b/compiler2/titanver
index d76fd1e43c331ae0520237d16497f13a5711b861..10e1f1cfad930b013fc85e7122e10cfa7b397155 100644
--- a/compiler2/titanver
+++ b/compiler2/titanver
@@ -113,7 +113,8 @@ if ( scalar keys %versions > 1 ) {
         warn "Compiled with $compiler $ver: ", join(', ', @$ref), "\n";
     }
     die "Error! All object files should be compiled with the same compiler version.\n"
-    . "The following $compiler versions were detected: ", join(', ', keys %versions);
+    . "The following $compiler versions were detected: ", join(', ', keys %versions),
+    "\nRun make clean and make to recompile the project if the version of the compiler changed recently.";
 }
 
 __END__
diff --git a/compiler2/ttcn3/compiler.c b/compiler2/ttcn3/compiler.c
index 1f029780b706e6a3c52f5b20125482a1badd46c8..aec9a10cadf91a8bf19351998eab012ee5a6d9e9 100644
--- a/compiler2/ttcn3/compiler.c
+++ b/compiler2/ttcn3/compiler.c
@@ -245,7 +245,8 @@ void write_output(output_struct *output, const char *module_name,
 	    "#if TTCN3_VERSION != %d\n"
 	    "#error Version mismatch detected.\\\n"
 	    " Please check the version of the %s compiler and the "
-	    "base library.\n"
+	    "base library.\\\n"
+	    " Run make clean and rebuild the project if the version of the compiler changed recently.\n"
 	    "#endif\n",
 	    TTCN3_VERSION, is_ttcn ? "TTCN-3" : "ASN.1");
 	/* Check the platform matches */