diff --git a/trimsp/src/TrimSPGUI/TrimSPGUI.pl b/trimsp/src/TrimSPGUI/TrimSPGUI.pl
index 860de7e..76fbf3e 100644
--- a/trimsp/src/TrimSPGUI/TrimSPGUI.pl
+++ b/trimsp/src/TrimSPGUI/TrimSPGUI.pl
@@ -2388,6 +2388,12 @@ sub CreateInpFile
 	my $Comp =  layerTable->text($i-1,0);
 	$All{$LComp} = $Comp;
 	my %LElComp=Chem::parse_formula($Comp);
+	foreach my $key (keys %LElComp) {
+# Check if composition is understood
+	    if ($key eq "" || Chem::Zof($key) eq "") {
+		$Check++;
+	    }  
+	}
 	if ($Comp eq "") {$Check++;}
 	
 # Densities of layers
@@ -2403,8 +2409,8 @@ sub CreateInpFile
 	if ($d eq "") {$Check++;}
 	
 # Sanity check, is the layer supposed to have value? are they all there?
-	if ($Check!=0) {
-	    my $ErrMsg="Error: Layer $i is empty. Expecting it to be defined!\n";
+	if ($Check!=0 ) {
+	    my $ErrMsg="Error: Bad chemical formula in Layer $i.\nPleach check!\n";
 	    print STDERR $ErrMsg;
 	    my $HelpWindow = Qt::MessageBox::information( this, "Error!",$ErrMsg);
 	    return "ERROR";
diff --git a/trimsp/src/TrimSPGUI4/TrimSPGUI4.pm b/trimsp/src/TrimSPGUI4/TrimSPGUI4.pm
index 7ffc42f..8b12acb 100644
--- a/trimsp/src/TrimSPGUI4/TrimSPGUI4.pm
+++ b/trimsp/src/TrimSPGUI4/TrimSPGUI4.pm
@@ -363,8 +363,7 @@ sub CreateInpFile
 # Check if composition is understood
 	    if ($key eq "" || Chem::Zof($key) eq "") {
 		$Check++;
-	    }
-	    
+	    }  
 	}
 	if ($Comp eq "") {$Check++;}
 # Write composition to results file header