diff --git a/src/rand_urandom_chacha20/rand_urandom_chacha20.c b/src/rand_urandom_chacha20/rand_urandom_chacha20.c
index caab249ce..02347ef0d 100755
--- a/src/rand_urandom_chacha20/rand_urandom_chacha20.c
+++ b/src/rand_urandom_chacha20/rand_urandom_chacha20.c
@@ -65,8 +65,8 @@ static OQS_RAND_urandom_chacha20_ctx *OQS_RAND_urandom_chacha20_ctx_new() {
 		goto err;
 	}
 #if defined(WINDOWS)
-	if (!CryptAcquireContext(&hCryptProv, NULL, NULL, PROV_RSA_FULL, 0) ||
-	        !CryptGenRandom(hCryptProv, 32, rand_ctx->key)) {
+	if (!CryptAcquireContext(&hCryptProv, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT) ||
+	    !CryptGenRandom(hCryptProv, 32, rand_ctx->key)) {
 		goto err;
 	}
 #else