diff --git a/src/ConEmuHk/Ansi.cpp b/src/ConEmuHk/Ansi.cpp
index 70e0e35d45..bd643bb31c 100644
--- a/src/ConEmuHk/Ansi.cpp
+++ b/src/ConEmuHk/Ansi.cpp
@@ -3831,6 +3831,8 @@ void CEAnsi::StorePromptBegin()
 //static
 CEAnsi* CEAnsi::Object(bool bForceCreate /*= false*/)
 {
+	CLastErrorGuard errGuard;
+
 	if (!AnsiTlsIndex)
 	{
 		AnsiTlsIndex = TlsAlloc();
diff --git a/src/common/HandleKeeper.cpp b/src/common/HandleKeeper.cpp
index 5bf6f850b2..4fdbf4f788 100644
--- a/src/common/HandleKeeper.cpp
+++ b/src/common/HandleKeeper.cpp
@@ -30,6 +30,7 @@ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include <windows.h>
 #include "HandleKeeper.h"
+#include "WErrGuard.h"
 
 #ifdef _DEBUG
 #include "MStrDup.h"
@@ -280,6 +281,8 @@ bool HandleKeeper::AllocHandleInfo(HANDLE h, HandleSource source, DWORD access,
 
 bool HandleKeeper::QueryHandleInfo(HANDLE h, HandleInformation& Info, bool AnsiOutExpected)
 {
+	CLastErrorGuard errGuard;
+
 	if (!h || (h == INVALID_HANDLE_VALUE))
 		return false;
 	bool bFound = false;
diff --git a/src/common/WCodePage.cpp b/src/common/WCodePage.cpp
index 9d1fdb338b..21faa739c0 100644
--- a/src/common/WCodePage.cpp
+++ b/src/common/WCodePage.cpp
@@ -30,6 +30,7 @@ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #define HIDE_USE_EXCEPTION_INFO
 #include "Common.h"
 #include "WCodePage.h"
+#include "WErrGuard.h"
 
 void CpCvt::ResetBuffer()
 {
@@ -38,6 +39,8 @@ void CpCvt::ResetBuffer()
 
 CpCvtResult CpCvt::SetCP(UINT anCP)
 {
+	CLastErrorGuard errGuard;
+
 	if (bInitialized && (nCP == anCP))
 		return ccr_OK;
 
@@ -93,7 +96,7 @@ CpCvtResult CpCvt::Convert(char c, wchar_t& wc)
 			}
 			goto wrap;
 		}
-		
+
 		// Continuation byte (10xxxxxx)?
 		if (blen && ((bt & 0xC0/*11xxxxxx*/) != 0x80/*10xxxxxx*/))
 		{