diff --git a/samples/vboxwrapper/vboxwrapper.cpp b/samples/vboxwrapper/vboxwrapper.cpp
index 764c405b1b..1d86bbb7ae 100644
--- a/samples/vboxwrapper/vboxwrapper.cpp
+++ b/samples/vboxwrapper/vboxwrapper.cpp
@@ -454,7 +454,7 @@ int main(int argc, char** argv) {
// Record if anonymous platform was used.
//
- if (boinc_file_exists(aid.project_dir + "/app_info.xml")) {
+ if (boinc_file_exists((std::string(aid.project_dir) + std::string("/app_info.xml")).c_str())) {
fprintf(
stderr,
"%s Detected: Anonymous Platform Enabled\n",
diff --git a/win_build/vboxwrapper.vcproj b/win_build/vboxwrapper.vcproj
index 543adeda00..8cfbaf2b3e 100644
--- a/win_build/vboxwrapper.vcproj
+++ b/win_build/vboxwrapper.vcproj
@@ -82,13 +82,13 @@
@@ -183,13 +183,13 @@