diff --git a/core/downloadfromdcthread.cpp b/core/downloadfromdcthread.cpp
index a9c8ce70b..8e937346d 100644
--- a/core/downloadfromdcthread.cpp
+++ b/core/downloadfromdcthread.cpp
@@ -71,6 +71,10 @@ void DownloadThread::run()
 	internalData->descriptor = descriptorLookup[m_data->vendor() + m_data->product()];
 	internalData->download_table = &downloadTable;
 	internalData->btname = strdup(m_data->devBluetoothName().toUtf8());
+	if (!internalData->descriptor) {
+		qDebug() << "No download possible when DC type is unknown";
+		return;
+	}
 #if defined(Q_OS_ANDROID)
 	// on Android we either use BT, a USB device, or we download via FTDI cable
 	if (!internalData->bluetooth_mode && (same_string(internalData->devname, "FTDI") || same_string(internalData->devname, "")))
diff --git a/mobile-widgets/qml/DownloadFromDiveComputer.qml b/mobile-widgets/qml/DownloadFromDiveComputer.qml
index 8a8bf2d74..729fe3c20 100644
--- a/mobile-widgets/qml/DownloadFromDiveComputer.qml
+++ b/mobile-widgets/qml/DownloadFromDiveComputer.qml
@@ -273,6 +273,8 @@ Kirigami.Page {
 			SsrfButton {
 				id: download
 				text: qsTr("Download")
+				enabled: comboVendor.currentIndex != -1 && comboProduct.currentIndex != -1 &&
+					 comboConnection.currentIndex != -1
 				onClicked: {
 					text = qsTr("Retry")
 					// strip any BT Name from the address