diff --git a/META-INF/2Pack.zip b/META-INF/2Pack.zip
index 3ebc258..fbdbf1a 100644
Binary files a/META-INF/2Pack.zip and b/META-INF/2Pack.zip differ
diff --git a/META-INF/MANIFEST.MF b/META-INF/MANIFEST.MF
index afc0134..ec5b6a3 100644
--- a/META-INF/MANIFEST.MF
+++ b/META-INF/MANIFEST.MF
@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: beluga.serverprint
 Bundle-SymbolicName: beluga.serverprint
-Bundle-Version: 5.0.0.qualifier
+Bundle-Version: 5.1.0.qualifier
 Service-Component: OSGI-INF/*.xml
 Bundle-RequiredExecutionEnvironment: JavaSE-11
 Require-Bundle: org.adempiere.base;bundle-version="5.1.0",
diff --git a/src/de/schoenbeck/serverprint/model/MPrinterProvider.java b/src/de/schoenbeck/serverprint/model/MPrinterProvider.java
index 85fad3f..702dc28 100644
--- a/src/de/schoenbeck/serverprint/model/MPrinterProvider.java
+++ b/src/de/schoenbeck/serverprint/model/MPrinterProvider.java
@@ -32,8 +32,8 @@ public MPrinterProvider(Properties ctx, ResultSet rs, String trxName) {
 	}
 
 	public List<MPrinter> getKnownPrinters() {
-		final String sql = "SELECT * FROM " + MPrinter.Table_Name
-						+ " WHERE " + MPrinterProvider.Table_Name + " = ?";
+		final String sql = "SELECT DISTINCT * FROM " + MPrinter.Table_Name
+						+ " WHERE " + MPrinter.COLUMNNAME_sbsp_printerprovider_ID + " = ?";
 		LinkedList<MPrinter> rtn = new LinkedList<>();
 
 		PreparedStatement ps = null;
diff --git a/src/de/schoenbeck/serverprint/printProvider/ServerPrintPrinterLookupProcess.java b/src/de/schoenbeck/serverprint/printProvider/ServerPrintPrinterLookupProcess.java
index 50e8302..1327626 100644
--- a/src/de/schoenbeck/serverprint/printProvider/ServerPrintPrinterLookupProcess.java
+++ b/src/de/schoenbeck/serverprint/printProvider/ServerPrintPrinterLookupProcess.java
@@ -25,13 +25,14 @@ protected String doIt() throws Exception {
 				.orElseThrow( () -> new NoSuchElementException("The provider does not exist.") );
 		var printers = lookupProcess.getAvailablePrinters(record_id, get_TrxName());
 		
-		var knownPrinters = new HashSet<Integer>();
-		for (int i : provider.getKnownPrinterIDs())
-			knownPrinters.add(i);
+		HashSet<MPrinter> knownPrinters = new HashSet<>(provider.getKnownPrinters());
 		
+		outerloop:
 		for (MPrinter p : printers) {
-			if (!knownPrinters.contains(p.get_ID()))
-				p.save();
+			for (var k : knownPrinters)
+				if (p.getValue().equals(k.getValue()))
+					break outerloop;
+			p.save();
 		}
 
 		//TODO: optionally show printers to user and let them select, which to keep