diff --git a/src/connection.ts b/src/connection.ts
index d810acb16..75e32252b 100644
--- a/src/connection.ts
+++ b/src/connection.ts
@@ -873,6 +873,7 @@ export interface ConnectionOptions {
 interface RoutingData {
   server: string;
   port: number;
+  instance: string;
 }
 
 /**
@@ -2484,7 +2485,7 @@ class Connection extends EventEmitter {
     }
 
     payload.hostname = this.config.options.workstationId || os.hostname();
-    payload.serverName = this.routingData ? this.routingData.server : this.config.server;
+    payload.serverName = this.routingData ? `${this.routingData.server}\\${this.routingData.instance}` : this.config.server;
     payload.appName = this.config.options.appName || 'Tedious';
     payload.libraryName = libraryName;
     payload.language = this.config.options.language;
diff --git a/src/login7-payload.ts b/src/login7-payload.ts
index 01b85f94c..899d0b583 100644
--- a/src/login7-payload.ts
+++ b/src/login7-payload.ts
@@ -251,15 +251,12 @@ class Login7Payload {
     }
 
     // (ibUnused / ibExtension): 2-byte
-    offset = fixedData.writeUInt16LE(dataOffset, offset);
+    const extensionOffsetHeaderOffset = offset;
+    offset = fixedData.writeUInt16LE(0, offset);
+
 
     // (cchUnused / cbExtension): 2-byte
-    const extensions = this.buildFeatureExt();
     offset = fixedData.writeUInt16LE(4, offset);
-    const extensionOffset = Buffer.alloc(4);
-    extensionOffset.writeUInt32LE(dataOffset += 4, 0);
-    dataOffset += extensions.length;
-    buffers.push(extensionOffset, extensions);
 
     // ibCltIntName: 2-byte
     offset = fixedData.writeUInt16LE(dataOffset, offset);
@@ -365,6 +362,13 @@ class Login7Payload {
       fixedData.writeUInt32LE(0, offset);
     }
 
+    fixedData.writeUInt16LE(dataOffset, extensionOffsetHeaderOffset);
+
+    const extensions = this.buildFeatureExt();
+    const extensionOffset = Buffer.alloc(4);
+    extensionOffset.writeUInt32LE(dataOffset + 4, 0);
+    buffers.push(extensionOffset, extensions);
+
     const data = Buffer.concat(buffers);
     data.writeUInt32LE(data.length, 0);
     return data;
diff --git a/src/token/handler.ts b/src/token/handler.ts
index 0c259a723..832e5bd4c 100644
--- a/src/token/handler.ts
+++ b/src/token/handler.ts
@@ -246,7 +246,7 @@ export class Login7TokenHandler extends TokenHandler {
   declare connection: Connection;
 
   declare fedAuthInfoToken: FedAuthInfoToken | undefined;
-  declare routingData: { server: string, port: number } | undefined;
+  declare routingData: { server: string, port: number, instance: string } | undefined;
 
   declare loginAckReceived: boolean;
 
@@ -337,10 +337,10 @@ export class Login7TokenHandler extends TokenHandler {
 
   onRoutingChange(token: RoutingEnvChangeToken) {
     // Removes instance name attached to the redirect url. E.g., redirect.db.net\instance1 --> redirect.db.net
-    const [ server ] = token.newValue.server.split('\\');
+    const [ server, instance ] = token.newValue.server.split('\\');
 
     this.routingData = {
-      server, port: token.newValue.port
+      server, port: token.newValue.port, instance
     };
   }