diff --git a/dlls/crypt32/crypt32.spec b/dlls/crypt32/crypt32.spec
index abeff355922..7d403943011 100644
--- a/dlls/crypt32/crypt32.spec
+++ b/dlls/crypt32/crypt32.spec
@@ -26,7 +26,7 @@
 @ stub CertDuplicateCRLContext
 @ stub CertDuplicateCTLContext
 @ stdcall CertDuplicateCertificateContext(ptr)
-@ stub CertDuplicateStore
+@ stdcall CertDuplicateStore(ptr)
 @ stub CertEnumCRLContextProperties
 @ stdcall CertEnumCRLsInStore(ptr ptr)
 @ stub CertEnumCTLContextProperties
diff --git a/dlls/crypt32/store.c b/dlls/crypt32/store.c
index 47e595ce9dd..b8a3d0f809d 100644
--- a/dlls/crypt32/store.c
+++ b/dlls/crypt32/store.c
@@ -2626,6 +2626,16 @@ PCCTL_CONTEXT WINAPI CertEnumCTLsInStore(HCERTSTORE hCertStore,
     return NULL;
 }
 
+HCERTSTORE WINAPI CertDuplicateStore(HCERTSTORE hCertStore)
+{
+    WINECRYPT_CERTSTORE *hcs = (WINECRYPT_CERTSTORE *)hCertStore;
+
+    TRACE("(%p)\n", hCertStore);
+
+    if (hcs && hcs->dwMagic == WINE_CRYPTCERTSTORE_MAGIC)
+        InterlockedIncrement(&hcs->ref);
+    return hCertStore;
+}
 
 BOOL WINAPI CertCloseStore(HCERTSTORE hCertStore, DWORD dwFlags)
 {
diff --git a/include/wincrypt.h b/include/wincrypt.h
index 678f46620af..9784223e9bc 100644
--- a/include/wincrypt.h
+++ b/include/wincrypt.h
@@ -2605,6 +2605,8 @@ BOOL WINAPI CertSetStoreProperty(HCERTSTORE hCertStore, DWORD dwPropId,
 BOOL WINAPI CertControlStore(HCERTSTORE hCertStore, DWORD dwFlags,
  DWORD dwCtrlType, void const *pvCtrlPara);
 
+HCERTSTORE WINAPI CertDuplicateStore(HCERTSTORE hCertStore);
+
 BOOL WINAPI CertCloseStore( HCERTSTORE hCertStore, DWORD dwFlags );
 
 BOOL WINAPI CertFreeCertificateContext( PCCERT_CONTEXT pCertContext );