diff --git a/Externals/crystaledit/editlib/ccrystaltextmarkers.h b/Externals/crystaledit/editlib/ccrystaltextmarkers.h
index e36ff601ccf..2850cec8153 100644
--- a/Externals/crystaledit/editlib/ccrystaltextmarkers.h
+++ b/Externals/crystaledit/editlib/ccrystaltextmarkers.h
@@ -19,10 +19,10 @@ class CCrystalTextMarkers
 	struct Marker
 	{
 		CString sFindWhat;
-		findtext_flags_t dwFlags;
-		enum COLORINDEX nBgColorIndex;
-		bool bUserDefined;
-		bool bVisible;
+		findtext_flags_t dwFlags = 0;
+		enum COLORINDEX nBgColorIndex = COLORINDEX_NONE;
+		bool bUserDefined = false;
+		bool bVisible = false;
 	};
 
 	CCrystalTextMarkers();
diff --git a/Src/7zCommon.cpp b/Src/7zCommon.cpp
index aff4d10927b..6108b49b596 100644
--- a/Src/7zCommon.cpp
+++ b/Src/7zCommon.cpp
@@ -341,6 +341,8 @@ SingleItemEnumerator::SingleItemEnumerator(const tchar_t* path, const tchar_t* F
 DirItemEnumerator::DirItemEnumerator(CDirView *pView, int nFlags)
 : m_pView(pView)
 , m_nFlags(nFlags)
+, m_nIndex(-1)
+, m_index(0)
 {
 	if (m_nFlags & Original)
 	{
diff --git a/Src/7zCommon.h b/Src/7zCommon.h
index 5c7ffc7aac9..22691aa6d96 100644
--- a/Src/7zCommon.h
+++ b/Src/7zCommon.h
@@ -27,7 +27,7 @@ Merge7z::Format *ArchiveGuessFormat(const String&);
 class CTempPathContext
 {
 public:
-	CTempPathContext *m_pParent;
+	CTempPathContext *m_pParent = nullptr;
 	String m_strDisplayRoot[3];
 	String m_strRoot[3];
 	CTempPathContext *DeleteHead();
diff --git a/Src/Common/ExConverter.h b/Src/Common/ExConverter.h
index 9dd46689aa6..e900a656d2e 100644
--- a/Src/Common/ExConverter.h
+++ b/Src/Common/ExConverter.h
@@ -5,11 +5,11 @@
 
 struct CodePageInfo
 {
-	int codepage;
+	int codepage = 0;
 	String desc;
 	String proportionalFont;
 	String fixedWidthFont;
-	char bGDICharset;
+	char bGDICharset = 0;
 };
 
 struct IExconverter
diff --git a/Src/Common/MessageBoxDialog.cpp b/Src/Common/MessageBoxDialog.cpp
index 970d48ed33d..6a381b2b264 100644
--- a/Src/Common/MessageBoxDialog.cpp
+++ b/Src/Common/MessageBoxDialog.cpp
@@ -353,7 +353,7 @@ CString CMessageBoxDialog::GenerateRegistryKey(UINT nMessageID, UINT nHelpID)
 struct ModelessMesssageBoxParam
 {
 	CString strMessage;
-	UINT nType;
+	UINT nType = 0;
 };
 
 /*
diff --git a/Src/Concurrent.h b/Src/Concurrent.h
index ba3953712bd..c380523f39c 100644
--- a/Src/Concurrent.h
+++ b/Src/Concurrent.h
@@ -10,10 +10,10 @@ namespace Concurrent
 		struct TaskParams
 		{
 			std::function<ResultType()> m_func;
-			HANDLE m_hThread;
-			ResultType m_result;
-			bool m_detached;
-			bool m_completed;
+			HANDLE m_hThread = nullptr;
+			ResultType m_result{};
+			bool m_detached = false;
+			bool m_completed = false;
 		};
 
 		explicit Task(TaskParams *pParams) : m_pParams(pParams)
diff --git a/Src/DirAdditionalPropertiesDlg.h b/Src/DirAdditionalPropertiesDlg.h
index 7677fa05458..82c9da3441a 100644
--- a/Src/DirAdditionalPropertiesDlg.h
+++ b/Src/DirAdditionalPropertiesDlg.h
@@ -17,8 +17,8 @@ struct Node
 	String name;
 	String canonicalName;
 	String displayName;
-	bool selected;
-	HTREEITEM hItem;
+	bool selected = false;
+	HTREEITEM hItem = nullptr;
 	std::list<Node> childNodes;
 };
 
diff --git a/Src/DirSelectFilesDlg.cpp b/Src/DirSelectFilesDlg.cpp
index d52e59b23a6..f4f8851eeee 100644
--- a/Src/DirSelectFilesDlg.cpp
+++ b/Src/DirSelectFilesDlg.cpp
@@ -125,7 +125,7 @@ void DirSelectFilesDlg::Impl::UpdateButtonCaptions()
 	}
 }
 
-DirSelectFilesDlg::DirSelectFilesDlg() : m_pimpl(new DirSelectFilesDlg::Impl(this)) {}
+DirSelectFilesDlg::DirSelectFilesDlg() : m_pimpl(new DirSelectFilesDlg::Impl(this)), m_pdi{} {}
 DirSelectFilesDlg::~DirSelectFilesDlg() = default;
 int DirSelectFilesDlg::DoModal() { return static_cast<int>(m_pimpl->DoModal()); }
 
diff --git a/Src/DirView.cpp b/Src/DirView.cpp
index 61325181d89..02c83b05ded 100644
--- a/Src/DirView.cpp
+++ b/Src/DirView.cpp
@@ -101,6 +101,7 @@ CDirView::CDirView()
 		, m_pColItems(nullptr)
 		, m_nActivePane(-1)
 		, m_nExpandSubdirs(DO_NOT_EXPAND)
+		, m_bUserCancelEdit(false)
 {
 	m_dwDefaultStyle &= ~LVS_TYPEMASK;
 	// Show selection all the time, so user can see current item even when
diff --git a/Src/FileActionScript.h b/Src/FileActionScript.h
index e357cc2fe17..ab5b826854b 100644
--- a/Src/FileActionScript.h
+++ b/Src/FileActionScript.h
@@ -38,6 +38,7 @@ struct FileAction
 	 */
 	enum ACT_TYPE
 	{ 
+		ACT_NONE = 0,
 		ACT_COPY = 1, /**< Copy the item(s). */
 		ACT_MOVE,     /**< Move the item(s). */
 		ACT_DEL,      /**< Delete the item(s). */
@@ -46,8 +47,8 @@ struct FileAction
 
 	String src; /**< Source for action */
 	String dest; /**< Destination action */
-	bool dirflag; /**< Is it directory? (`true` means directory) */
-	ACT_TYPE atype; /**< Action's type */
+	bool dirflag = false; /**< Is it directory? (`true` means directory) */
+	ACT_TYPE atype = ACT_NONE; /**< Action's type */
 };
 
 /** 
@@ -75,10 +76,10 @@ struct FileActionItem : public FileAction
 	 * This is an arbitrary value that can be used to associate the item with
 	 * other items. This can be e.g. indext of the item in the GUI.
 	 */
-	int context;
-	int UIResult; /**< Resulting UI action */
-	int UIOrigin; /**< Original UI-side */
-	int UIDestination; /**< Destination UI-side */
+	int context = 0;
+	int UIResult = 0; /**< Resulting UI action */
+	int UIOrigin = 0; /**< Original UI-side */
+	int UIDestination = 0; /**< Destination UI-side */
 };
 
 /** 
diff --git a/Src/LocationView.h b/Src/LocationView.h
index 089a08e21c9..575a7fa789f 100644
--- a/Src/LocationView.h
+++ b/Src/LocationView.h
@@ -16,14 +16,14 @@ class CMergeEditView;
  */
 struct MovedLine
 {
-	int apparent0;
-	int apparent1;
-	int blockHeight;
+	int apparent0 = 0;
+	int apparent1 = 0;
+	int blockHeight = 0;
 	CPoint ptLeftUpper;
 	CPoint ptLeftLower;
 	CPoint ptRightUpper;
 	CPoint ptRightLower;
-	bool currentDiff;
+	bool currentDiff = false;
 };
 
 typedef CList<MovedLine, MovedLine&> MOVEDLINE_LIST;
diff --git a/Src/OpenView.cpp b/Src/OpenView.cpp
index 6ff8ae525fb..752aaa639e2 100644
--- a/Src/OpenView.cpp
+++ b/Src/OpenView.cpp
@@ -1083,7 +1083,7 @@ void COpenView::SaveComboboxStates()
 
 struct UpdateButtonStatesThreadParams
 {
-	HWND m_hWnd;
+	HWND m_hWnd = nullptr;
 	PathContext m_paths;
 };
 
diff --git a/Src/SubstitutionFiltersList.h b/Src/SubstitutionFiltersList.h
index 7fc86d59342..e6762d3a969 100644
--- a/Src/SubstitutionFiltersList.h
+++ b/Src/SubstitutionFiltersList.h
@@ -17,10 +17,10 @@ class COptionsMgr;
  */
 struct SubstitutionFilter
 {
-	bool enabled;
-	bool useRegExp;
-	bool caseSensitive;
-	bool matchWholeWordOnly;
+	bool enabled = false;
+	bool useRegExp = false;
+	bool caseSensitive = false;
+	bool matchWholeWordOnly = false;
 	String pattern;
 	String replacement;
 };