diff --git a/iturhfprop-service/Dockerfile b/iturhfprop-service/Dockerfile
index 5630bb4..eee6a85 100644
--- a/iturhfprop-service/Dockerfile
+++ b/iturhfprop-service/Dockerfile
@@ -7,6 +7,7 @@ ENV DEBIAN_FRONTEND=noninteractive
 RUN apt-get update && apt-get install -y \
     curl \
     tar \
+    unzip \
     ca-certificates \
     findutils \
     && curl -fsSL https://deb.nodesource.com/setup_20.x | bash - \
@@ -22,33 +23,26 @@ RUN curl -L -o ITURHFProp "https://github.com/ITU-R-Study-Group-3/ITU-R-HF/relea
     && curl -L -o libp372.so "https://github.com/ITU-R-Study-Group-3/ITU-R-HF/releases/download/v14.3/libp372.so" \
     && chmod +x ITURHFProp
 
-# Download source to get Data files
-RUN curl -L -o source.tar.gz "https://github.com/ITU-R-Study-Group-3/ITU-R-HF/archive/refs/tags/v14.3.tar.gz" \
-    && tar -xzf source.tar.gz \
-    && echo "=== Finding all Data directories ===" \
-    && find ITU-R-HF-14.3 -type d -name "Data" \
-    && echo "=== Finding ionos files ===" \
-    && find ITU-R-HF-14.3 -name "ionos*.bin" \
-    && echo "=== Finding ant files ===" \
-    && find ITU-R-HF-14.3 -name "*.ant" \
-    && echo "=== Finding COEFF files ===" \
-    && find ITU-R-HF-14.3 -name "COEFF*.BIN" | head -5
+# Download source to get Data files from official ITU download
+RUN curl -L -o itu-hf.zip "https://www.itu.int/en/ITU-R/study-groups/rsg3/rwp3m/Software%20Products/ITU-R-HF_14.3.zip" \
+    && unzip itu-hf.zip \
+    && echo "=== Contents of ITU download ===" \
+    && ls -la \
+    && echo "=== Looking for Data directory ===" \
+    && find . -type d -name "Data" \
+    && echo "=== Looking for ionos files ===" \
+    && find . -name "ionos*.bin" \
+    && find . -name "*.ant"
 
-# Create Data directory and copy ALL required files from various locations
-RUN mkdir -p Data \
-    && echo "=== Copying COEFF files ===" \
-    && find ITU-R-HF-14.3 -name "COEFF*.BIN" -exec cp {} Data/ \; \
-    && find ITU-R-HF-14.3 -name "COEFF*.txt" -exec cp {} Data/ \; \
-    && echo "=== Copying ionos files ===" \
-    && find ITU-R-HF-14.3 -name "ionos*.bin" -exec cp {} Data/ \; \
-    && echo "=== Copying antenna files ===" \
-    && find ITU-R-HF-14.3 -name "*.ant" -exec cp {} Data/ \; \
-    && echo "=== Copying any other data files ===" \
-    && find ITU-R-HF-14.3 -name "P372*.txt" -exec cp {} Data/ \; 2>/dev/null || true \
-    && find ITU-R-HF-14.3 -name "*.csv" -exec cp {} Data/ \; 2>/dev/null || true
+# Copy all data files from ITU download
+RUN if [ -d "Data" ]; then echo "Found Data at root"; \
+    elif [ -d "ITU-R-HF_14.3/Data" ]; then mv ITU-R-HF_14.3/Data .; \
+    elif [ -d "P533/Data" ]; then mv P533/Data .; \
+    else find . -type d -name "Data" -exec cp -r {} . \; ; fi \
+    && echo "=== Final Data contents ===" && ls -la Data/ | head -20
 
 # Cleanup
-RUN rm -rf ITU-R-HF-14.3 source.tar.gz
+RUN rm -rf ITU-R-HF_14.3 itu-hf.zip P533 *.exe *.dll 2>/dev/null || true
 
 # Set library path so ITURHFProp can find shared libs
 ENV LD_LIBRARY_PATH=/opt/iturhfprop:$LD_LIBRARY_PATH
diff --git a/iturhfprop-service/server.js b/iturhfprop-service/server.js
index 17fe053..36e0fb0 100644
--- a/iturhfprop-service/server.js
+++ b/iturhfprop-service/server.js
@@ -95,7 +95,7 @@ Path.Relr ${requiredReliability}
 Path.ManMadeNoise ${manMadeNoise}
 Path.Modulation ANALOG
 Path.SorL SHORTPATH
-DataFilePath ${ITURHFPROP_DATA}/Data/
+DataFilePath "${ITURHFPROP_DATA}/Data/"
 `;
 
   return input;
@@ -350,6 +350,58 @@ app.get('/api/diag', async (req, res) => {
     results.testRun.usage = { error: e.message, stderr: e.stderr?.toString(), stdout: e.stdout?.toString() };
   }
   
+  // List ALL files in Data directory
+  try {
+    const allDataFiles = fs.readdirSync(ITURHFPROP_DATA + '/Data');
+    results.data.allFiles = allDataFiles;
+    results.data.hasIonos = allDataFiles.some(f => f.includes('ionos'));
+    results.data.hasAnt = allDataFiles.some(f => f.endsWith('.ant'));
+    results.data.fileCount = allDataFiles.length;
+  } catch (e) {
+    results.data.allFiles = { error: e.message };
+  }
+  
+  // Create a minimal test input file and try to run
+  try {
+    const { execSync } = require('child_process');
+    const testInput = `Path.L_tx.lat 40.0
+Path.L_tx.lng -75.0
+Path.L_rx.lat 51.0
+Path.L_rx.lng 0.0
+Path.year 2026
+Path.month 2
+Path.hour 12
+Path.SSN 100
+Path.frequency 14.0
+Path.txpower -10.0
+Path.BW 3000
+Path.SNRr 15
+Path.Relr 90
+Path.ManMadeNoise RESIDENTIAL
+Path.Modulation ANALOG
+Path.SorL SHORTPATH
+DataFilePath "${ITURHFPROP_DATA}/Data/"
+`;
+    fs.writeFileSync('/tmp/test_input.txt', testInput);
+    results.testRun.inputFile = testInput.split('\n');
+    
+    const testOutput = execSync(`${ITURHFPROP_PATH} /tmp/test_input.txt /tmp/test_output.txt 2>&1 || echo "Exit code: $?"`, {
+      encoding: 'utf8',
+      env: { ...process.env, LD_LIBRARY_PATH: '/opt/iturhfprop' }
+    });
+    results.testRun.testExec = testOutput.split('\n').slice(0, 20);
+    
+    // Check if output was created
+    if (fs.existsSync('/tmp/test_output.txt')) {
+      const output = fs.readFileSync('/tmp/test_output.txt', 'utf8');
+      results.testRun.testOutput = output.split('\n').slice(0, 20);
+    } else {
+      results.testRun.testOutput = 'No output file created';
+    }
+  } catch (e) {
+    results.testRun.testExec = { error: e.message, stderr: e.stderr?.toString(), stdout: e.stdout?.toString() };
+  }
+  
   res.json(results);
 });