diff --git a/main.cpp b/main.cpp
index fe8ea292..45da2f3e 100644
--- a/main.cpp
+++ b/main.cpp
@@ -239,6 +239,9 @@ int main(int argc, char **argv)
             case simplecpp::Output::DUI_ERROR:
                 std::cerr << "dui error: ";
                 break;
+            case simplecpp::Output::CACHE_ERROR:
+                std::cerr << "cache error: ";
+                break;
             }
             std::cerr << output.msg << std::endl;
         }
diff --git a/simplecpp.cpp b/simplecpp.cpp
index ef891eb1..5d6a1a0b 100644
--- a/simplecpp.cpp
+++ b/simplecpp.cpp
@@ -53,8 +53,10 @@
 #include <vector>
 
 #ifdef _WIN32
+#  include <system_error>
 #  include <direct.h>
 #else
+#  include <cerrno>
 #  include <sys/stat.h>
 #endif
 
@@ -3051,8 +3053,18 @@ std::pair<simplecpp::FileData *, bool> simplecpp::FileDataCache::tryload(FileDat
     const std::string &path = name_it->first;
     FileID fileId;
 
-    if (!getFileId(path, fileId))
+    std::string errmsg;
+    if (!getFileId(path, fileId, errmsg)) {
+        if (outputList && !errmsg.empty()) {
+            simplecpp::Output err = {
+                Output::CACHE_ERROR,
+                Location{filenames},
+                "Failed to get ID for " + path + " (" + errmsg + ")"
+            };
+            outputList->push_back(std::move(err));
+        }
         return {nullptr, false};
+    }
 
     const auto id_it = mIdMap.find(fileId);
     if (id_it != mIdMap.end()) {
@@ -3118,15 +3130,23 @@ std::pair<simplecpp::FileData *, bool> simplecpp::FileDataCache::get(const std::
     return {nullptr, false};
 }
 
-bool simplecpp::FileDataCache::getFileId(const std::string &path, FileID &id)
-{
+bool simplecpp::FileDataCache::getFileId(const std::string &path, FileID &id, std::string& errmsg) {
+    errmsg = "";
+
 #ifdef _WIN32
     HANDLE hFile = CreateFileA(path.c_str(), 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
-
-    if (hFile == INVALID_HANDLE_VALUE)
+    if (hFile == INVALID_HANDLE_VALUE) {
+        const DWORD err = GetLastError();
+        if (err != ERROR_FILE_NOT_FOUND)
+            errmsg = "CreateFileA() failed with '" + std::system_category().message(err) + "'";
         return false;
+    }
 
     const BOOL ret = GetFileInformationByHandleEx(hFile, FileIdInfo, &id.fileIdInfo, sizeof(id.fileIdInfo));
+    if (!ret) {
+        const DWORD err = GetLastError();
+        errmsg = "GetFileInformationByHandleEx() failed with '" + std::system_category().message(err) + "'";
+    }
 
     CloseHandle(hFile);
 
@@ -3134,8 +3154,12 @@ bool simplecpp::FileDataCache::getFileId(const std::string &path, FileID &id)
 #else
     struct stat statbuf;
 
-    if (stat(path.c_str(), &statbuf) != 0)
+    if (stat(path.c_str(), &statbuf) == -1) {
+        const int err = errno;
+        if (err != ENOENT)
+            errmsg = std::string("stat() failed with '") + strerror(err) + "'";
         return false;
+    }
 
     id.dev = statbuf.st_dev;
     id.ino = statbuf.st_ino;
diff --git a/simplecpp.h b/simplecpp.h
index 22f3c19f..cf57e48d 100644
--- a/simplecpp.h
+++ b/simplecpp.h
@@ -211,7 +211,8 @@ namespace simplecpp {
             UNHANDLED_CHAR_ERROR,
             EXPLICIT_INCLUDE_NOT_FOUND,
             FILE_NOT_FOUND,
-            DUI_ERROR
+            DUI_ERROR,
+            CACHE_ERROR
         } type;
         Output(Type type, const Location& loc, std::string msg) : type(type), location(loc), msg(std::move(msg)) {}
         Location location;
@@ -501,7 +502,7 @@ namespace simplecpp {
         using name_map_type = std::unordered_map<std::string, FileData *>;
         using id_map_type = std::unordered_map<FileID, FileData *, FileID::Hasher>;
 
-        static bool getFileId(const std::string &path, FileID &id);
+        static bool getFileId(const std::string &path, FileID &id, std::string& errmsg);
 
         std::pair<FileData *, bool> tryload(name_map_type::iterator &name_it, const DUI &dui, std::vector<std::string> &filenames, OutputList *outputList);
 
diff --git a/test.cpp b/test.cpp
index 69e08781..828dd169 100644
--- a/test.cpp
+++ b/test.cpp
@@ -167,6 +167,9 @@ static std::string toString(const simplecpp::OutputList &outputList)
         case simplecpp::Output::Type::DUI_ERROR:
             ostr << "dui_error,";
             break;
+        case simplecpp::Output::Type::CACHE_ERROR:
+            ostr << "cache_error,";
+            break;
         }
 
         ostr << output.msg << '\n';