diff --git a/alfa-xdomea/src/main/java/de/ozgcloud/alfa/export/ExportService.java b/alfa-xdomea/src/main/java/de/ozgcloud/alfa/export/ExportService.java
index 416cf6fdd698d31657fd1eac79fbf046caa7e9e5..3f5690be1f58840a358a13f484043a279d3ed3ff 100644
--- a/alfa-xdomea/src/main/java/de/ozgcloud/alfa/export/ExportService.java
+++ b/alfa-xdomea/src/main/java/de/ozgcloud/alfa/export/ExportService.java
@@ -51,9 +51,10 @@ class ExportService {
 		var abgabe = AbgabeCreator.createAbgabeCreator()
 				.withKopf(exportVorgangService.createKopf(vorgangWithEingang))
 				.withVorgang(exportVorgangService.createVorgangType(vorgangWithEingang))
-				.withDokumentTypes(exportFileService.createDokumentTypes(ozgFiles, vorgangWithEingang.getEingang().getHeader().getFormEngineName()))
+				.withDokumentTypes(
+						exportFileService.createDokumentTypes(ozgFiles.stream(), vorgangWithEingang.getEingang().getHeader().getFormEngineName()))
 				.create();
-		return ExportData.builder().abgabe(abgabe).exportFilename(buildXmlFilename(filenameId)).exportFiles(ozgFiles).build();
+		return ExportData.builder().abgabe(abgabe).exportFilename(buildXmlFilename(filenameId)).exportFiles(ozgFiles.stream()).build();
 	}
 
 	String buildXmlFilename(String filenameId) {
@@ -93,7 +94,7 @@ class ExportService {
 			exportFileService.writeOzgFile(ozgFile.getId(), zipOutputStream);
 			zipOutputStream.closeEntry();
 		} catch (IOException e) {
-			throw new RuntimeException(e);
+			throw new TechnicalException("Cannot add file to ZIP.", e);
 		}
 	}
 
@@ -101,7 +102,7 @@ class ExportService {
 		try (var fileInputStream = new FileInputStream(file)) {
 			fileInputStream.transferTo(outputStream);
 		} catch (Exception e) {
-			throw new TechnicalException("Error writting XDomea zip file to output stream", e);
+			throw new TechnicalException("Error writing XDomea zip file to output stream", e);
 		}
 	}
 }
diff --git a/alfa-xdomea/src/main/java/de/ozgcloud/alfa/file/ExportFileService.java b/alfa-xdomea/src/main/java/de/ozgcloud/alfa/file/ExportFileService.java
index c224b6c04fdb5fda786fca7dea4bf3f65a08edab..c196597c3074a43243b137b08a25d2165832fcf9 100644
--- a/alfa-xdomea/src/main/java/de/ozgcloud/alfa/file/ExportFileService.java
+++ b/alfa-xdomea/src/main/java/de/ozgcloud/alfa/file/ExportFileService.java
@@ -1,6 +1,7 @@
 package de.ozgcloud.alfa.file;
 
 import java.io.OutputStream;
+import java.util.List;
 import java.util.function.Predicate;
 import java.util.stream.Stream;
 
@@ -17,7 +18,7 @@ import de.xoev.xdomea.DokumentType;
 @Service
 public class ExportFileService {
 
-	private static final Predicate<OzgFile> IS_PDF_FILE = file -> file.getContentType().equals(MediaType.APPLICATION_PDF_VALUE);
+	private static final Predicate<OzgFile> IS_PDF_FILE = file -> MediaType.APPLICATION_PDF_VALUE.equals(file.getContentType());
 
 	@Autowired
 	private OzgFileService ozgFileService;
@@ -28,10 +29,10 @@ public class ExportFileService {
 	@Autowired
 	private DokumentTypeCreator dokumentTypeCreator;
 
-	public Stream<OzgFile> getAllPdfs(String eingangId) {
+	public List<OzgFile> getAllPdfs(String eingangId) {
 		var representations = ozgFileService.getRepresentationsByEingang(eingangId);
 		var attachments = ozgFileService.getAttachmentsByEingang(eingangId);
-		return Stream.concat(representations, attachments).filter(IS_PDF_FILE);
+		return Stream.concat(representations, attachments).filter(IS_PDF_FILE).toList();
 	}
 
 	public Stream<DokumentType> createDokumentTypes(Stream<OzgFile> ozgFileStream, String formEngineName) {
diff --git a/alfa-xdomea/src/test/java/de/ozgcloud/alfa/export/ExportServiceTest.java b/alfa-xdomea/src/test/java/de/ozgcloud/alfa/export/ExportServiceTest.java
index 2a09022daa695900b8d0818ec1ff4919727157e3..342b1d2e6d5166a7062787664826cfb032e5bd86 100644
--- a/alfa-xdomea/src/test/java/de/ozgcloud/alfa/export/ExportServiceTest.java
+++ b/alfa-xdomea/src/test/java/de/ozgcloud/alfa/export/ExportServiceTest.java
@@ -9,6 +9,7 @@ import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import java.util.List;
 import java.util.UUID;
 import java.util.stream.Stream;
 import java.util.zip.ZipEntry;
@@ -128,7 +129,9 @@ class ExportServiceTest {
 			when(exportVorgangService.getVorgang(any())).thenReturn(vorgang);
 			when(exportVorgangService.createVorgangType(any())).thenReturn(vorgangType);
 			when(exportVorgangService.createKopf(any())).thenReturn(kopfType);
-			when(exportFileService.getAllPdfs(any())).thenReturn(ozgFiles);
+			List<OzgFile> ozgFileList = mock(List.class);
+			when(ozgFileList.stream()).thenReturn(ozgFiles);
+			when(exportFileService.getAllPdfs(any())).thenReturn(ozgFileList);
 			when(exportFileService.createDokumentTypes(any(), any())).thenReturn(dokumentTypes);
 			doReturn(FILE_NAME).when(service).buildXmlFilename(any());
 			abgabeCreatorStatic = mockStatic(AbgabeCreator.class);