diff --git a/slsDetectorSoftware/src/Detector.cpp b/slsDetectorSoftware/src/Detector.cpp
index b124dd23b..3ad9108cb 100644
--- a/slsDetectorSoftware/src/Detector.cpp
+++ b/slsDetectorSoftware/src/Detector.cpp
@@ -2189,7 +2189,7 @@ void Detector::updateFirmwareAndServer(const std::string &sname,
                                        Positions pos) {
     LOG(logINFO) << "Updating Firmware and Detector Server (no tftp)...";
     LOG(logINFO) << "Updating Detector Server (no tftp)...";
-    std::vector<char> buffer = readBinaryFile(fname, "Update Detector Server");
+    std::vector<char> buffer = readBinaryFile(sname, "Update Detector Server");
     std::string filename = sls::getFileNameFromFilePath(sname);
     pimpl->Parallel(&Module::updateDetectorServer, pos, buffer, filename);
     programFPGA(fname, pos);