# gRPC based apps (such as Zap) won't connect to lnd

Applies to:

nodl OG, nodl One (black, etched logo) and nodl Dojo (red, etched logo)

# Symptoms

After clicking the lnd connect link or scanning the QR code, an error occurs and the wallet won't connect to lnd.

# Cause

There are two probable causes. The TLS certificate may be invalid (for example when the IP address of the device changed or because it has been running for more than a year) or the TCP proxy (nginx) in front of lnd is stuck.

# Solution

First, [ssh into your nodl] as root(https://docs.nodl.it/guides/ssh.html)

Then, try restarting nginx with the following command:

service nginx restart

If your wallet still can't connect, try:


Then restart lnd in the nodl web interface.