diff --git a/Library/ConfigParser.cpp b/Library/ConfigParser.cpp
index 942cc3ae..5739ed91 100644
--- a/Library/ConfigParser.cpp
+++ b/Library/ConfigParser.cpp
@@ -759,7 +759,14 @@ double CConfigParser::ReadFormula(LPCTSTR section, LPCTSTR key, double defValue)
 		char* errMsg = MathParser_Parse(m_Parser, ConvertToAscii(result.substr(1, result.size() - 2).c_str()).c_str(), &resultValue);
 		if (errMsg != NULL)
 		{
-			Log(LOG_ERROR, ConvertToWide(errMsg).c_str());
+			std::wstring error = L"ReadFormula: ";
+			error += ConvertToWide(errMsg);
+			error += L" in key \"";
+			error += key ? key : L"";
+			error += L"\" in section [";
+			error += section ? section : L"";
+			error += L"].";
+			Log(LOG_ERROR, error.c_str());
 		}
 
 		return resultValue;
@@ -778,7 +785,11 @@ bool CConfigParser::ReadFormula(const std::wstring& result, double* resultValue)
 		char* errMsg = MathParser_Parse(m_Parser, ConvertToAscii(result.substr(1, result.size() - 2).c_str()).c_str(), resultValue);
 		if (errMsg != NULL)
 		{
-			Log(LOG_ERROR, ConvertToWide(errMsg).c_str());
+			std::wstring error = L"ReadFormula: ";
+			error += ConvertToWide(errMsg);
+			error += L": ";
+			error += result;
+			Log(LOG_ERROR, error.c_str());
 			return false;
 		}
 
diff --git a/Library/MeasureCalc.cpp b/Library/MeasureCalc.cpp
index 0b14d988..ce431c02 100644
--- a/Library/MeasureCalc.cpp
+++ b/Library/MeasureCalc.cpp
@@ -82,7 +82,12 @@ bool CMeasureCalc::Update()
 	char* errMsg = MathParser_Parse(m_Parser, ConvertToAscii(m_Formula.c_str()).c_str(), &m_Value);
 	if (errMsg != NULL)
 	{
-		Log(LOG_ERROR, ConvertToWide(errMsg).c_str());
+		std::wstring error = L"Calc: ";
+		error += ConvertToWide(errMsg);
+		error += L" in measure [";
+		error += m_Name;
+		error += L"].";
+		Log(LOG_ERROR, error.c_str());
 	}
 
 	return PostUpdate();
diff --git a/Library/Rainmeter.cpp b/Library/Rainmeter.cpp
index f1d7f191..a8bfe0a6 100644
--- a/Library/Rainmeter.cpp
+++ b/Library/Rainmeter.cpp
@@ -3781,7 +3781,7 @@ void CRainmeter::ShowContextMenu(POINT pos, CMeterWindow* meterWindow)
 				{
 					if (!m_ConfigMenu.empty())
 					{
-						DeleteMenu(configMenu, 0, MF_BYPOSITION);
+						DeleteMenu(configMenu, 0, MF_BYPOSITION);  // "No skins available" menuitem
 						CreateConfigMenu(configMenu, m_ConfigMenu);
 					}
 
@@ -3796,7 +3796,7 @@ void CRainmeter::ShowContextMenu(POINT pos, CMeterWindow* meterWindow)
 				{
 					if (!m_Themes.empty())
 					{
-						DeleteMenu(themeMenu, 0, MF_BYPOSITION);
+						DeleteMenu(themeMenu, 0, MF_BYPOSITION);  // "No themes available" menuitem
 						CreateThemeMenu(themeMenu);
 					}
 				}
@@ -3926,12 +3926,9 @@ HMENU CRainmeter::CreateConfigMenu(HMENU configMenu, std::vector<CONFIGMENU>& co
 
 void CRainmeter::CreateThemeMenu(HMENU themeMenu)
 {
-	if (!m_Themes.empty())
+	for (size_t i = 0, isize = m_Themes.size(); i < isize; ++i)
 	{
-		for (size_t i = 0, isize = m_Themes.size(); i < isize; ++i)
-		{
-			InsertMenu(themeMenu, i, MF_BYPOSITION, ID_THEME_FIRST + i, m_Themes[i].c_str());
-		}
+		InsertMenu(themeMenu, i, MF_BYPOSITION, ID_THEME_FIRST + i, m_Themes[i].c_str());
 	}
 }