diff --git a/NEWS.md b/NEWS.md
index ef8fc383..2945c93e 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -8,6 +8,7 @@ Version 0.7.3
  - enhancement: "use utf8 by default" in editor's misc setting
  - fix: syntax issues not correctly cleared when the file was saved as another name.
  - enhancement: when running a program, redirect a data file to its stdin
+ - fix: can't correctly handle '&&' and '||' in the #if directive (and correctly parse windows.h header file)
 
 Version 0.7.2
  - fix: rainbow parenthesis stop functioning when change editor's general options
diff --git a/RedPandaIDE/parser/cpppreprocessor.cpp b/RedPandaIDE/parser/cpppreprocessor.cpp
index 78ee0c0e..6967394b 100644
--- a/RedPandaIDE/parser/cpppreprocessor.cpp
+++ b/RedPandaIDE/parser/cpppreprocessor.cpp
@@ -1320,21 +1320,21 @@ bool CppPreprocessor::evalNumber(const QString &expr, int &result, int &pos)
 
     if (s.endsWith("LL",Qt::CaseInsensitive)) {
         s.remove(s.length()-2,2);
-        result = s.toLongLong(&ok,0);
+        result = s.toLongLong(&ok);
     } else if (s.endsWith("L",Qt::CaseInsensitive)) {
         s.remove(s.length()-1,1);
-        result = s.toLong(&ok,0);
+        result = s.toLong(&ok);
     } else if (s.endsWith("ULL",Qt::CaseInsensitive)) {
         s.remove(s.length()-3,3);
-        result = s.toULongLong(&ok,0);
+        result = s.toULongLong(&ok);
     } else if (s.endsWith("UL",Qt::CaseInsensitive)) {
         s.remove(s.length()-2,2);
-        result = s.toULong(&ok,0);
+        result = s.toULong(&ok);
     } else if (s.endsWith("U",Qt::CaseInsensitive)) {
         s.remove(s.length()-1,1);
-        result = s.toUInt(&ok,0);
+        result = s.toUInt(&ok);
     } else {
-        result = s.toInt(&ok,0);
+        result = s.toInt(&ok);
     }
     return ok;
 }
@@ -1578,7 +1578,9 @@ bool CppPreprocessor::evalBitAndExpr(const QString &expr, int &result, int &pos)
     while (true) {
         if (!skipSpaces(expr,pos))
             break;
-        if (expr[pos]=='&') {
+        if (expr[pos]=='&'
+                && (pos == expr.length()
+                || expr[pos+1]!='&')) {
             pos++;
             int rightResult;
             if (!evalEqualExpr(expr,rightResult,pos))
@@ -1626,7 +1628,9 @@ bool CppPreprocessor::evalBitOrExpr(const QString &expr, int &result, int &pos)
     while (true) {
         if (!skipSpaces(expr,pos))
             break;
-        if (expr[pos] == '|') {
+        if (expr[pos] == '|'
+                && (pos == expr.length()
+                || expr[pos+1]!='|')) {
             pos++;
             int rightResult;
             if (!evalBitXorExpr(expr,rightResult,pos))