“Invalid token format” Error and 500 Errors

Hello,

When I try to login (Even when I try to go the plugins page in wp-admin) I get a 500 error. I also got an error when I tried to go to my WP-Admin plugins page (Don’t remember the error). I tried to revoke and reauthenticate, and it did work for a time, but probably only a few days. It broke again, so I had to disable the plugin. I really want to use it, but I can’t because the error is confusing my users and causing other issues.

Here is my system info:

OS: Linux ip-###-##-##-## 4.4.0-1032-aws #41-Ubuntu SMP Mon Aug 14 13:08:44 UTC 2017 x86_64
PHP version: 7.0.22-0ubuntu0.16.04.1
WordPress version: 4.8.1
WordPress multisite: No
openssl: Available
allow_url_fopen: Enabled
stream_socket_client: Available
fsockopen: Available
cURL: Available
cURL Version: 7.47.0, OpenSSL/1.0.2g

Here is the error:

Notice: Undefined index: refresh_token in /var/www/html/———————/wp-content/plugins/gmail-smtp/main.php on line 681

Fatal error: Uncaught InvalidArgumentException: Invalid token format in /var/www/html/———————-/wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Client.php:434 Stack trace: #0 /var/www/html/———————-/wp-content/plugins/gmail-smtp/class.phpmaileroauthgoogle.php(138): Google_Client->setAccessToken(Array) #1 /var/www/html/———————-/wp-content/plugins/gmail-smtp/PHPMailer/class.smtp.php(470): GmailXOAuth2->getOauth64() #2 /var/www/html/———————-/wp-content/plugins/gmail-smtp/class.phpmaileroauth.php(152): SMTP->authenticate(”, ”, ‘XOAUTH2’, ”, ”, Object(GmailXOAuth2)) #3 /var/www/html/———————-/wp-content/plugins/gmail-smtp/PHPMailer/class.phpmailer.php(1540): PHPMailerOAuth->smtpConnect(Array) #4 /var/www/html/———————-/wp-content/plugins/gmail-smtp/PHPMailer/class.phpmailer.php(1335): PHPMailer->smtpSend(‘Date: Fri, 15 S…’, ‘This email was …’) #5 /var/www/html/———————-/wp-content/plug in /var/www/html/———————-/wp-content/plugins/gmail-smtp/google-api-php-client/src/Google/Client.php on line 434