We are currently experiencing an outage. We're aware of the problem and are working to fix it.

[Click here for Latest Info on Service Outages]

Recent Service Interruption on 2/4/2025: We are currently functioning normally.

[Click here for Latest Updates on Service Interruptions]

Maintenance Alert: SupportSync will be performing scheduled maintenance on 12/16/2023 between 11PM and 12PM PST. During this time period, SupportSync may be unavailable.
FedEx is currently experiencing an outage. They're aware of the problem and are working to fix it.
There is currently a problem sending to the YAHOO.COM domain. Yahoo servers are blocking our emails to customers. We're aware of the problem and are working to fix it.

UPS Shipping: Action Required for your Account. UPS Now Requires OAuth 2: [See Latest UPS Setup Instructions]
FedEx Shipping Error: "ERROR: [1000] Authentication Failed."   [Click here for latest info]

Yahoo Blocking SupportSync Emails

Update 6/10/2025:

We detected phishing attack as follows:

First, attack bots take advantage of WEAK passwords to login.

Then, they exploit the form to Test Email Templates.


To address this, we're making the following changes:

- Add Rate Limits to our email server.

- Identify and Ban Malicious IPs.

- Add Security Keys to Cookies.

- Increase Password Strength.

- Force Password Reset for ALL.

- Only Allow Email Tests to User's Email Address.

- Notify users of logins to their accounts.


Update 6/5/2025: 

We discovered malicious activity and added these IPs to our Block List:

85.28.127.229, 86.104.252.46, 105.129.231.29, 149.154.161.246, 160.164.210.78, 163.5.160.152, 196.81.91.148, 197.253.242.28, 197.253.217.204, 197.253.241.161  


Update 6/4/2025: 

We completed the Yahoo Sender Form on the Yahoo Sender Hub for assistance.


6/4/2025:

We are experiencing Yahoo blocking our emails to customers.


We're receiving errors from Yahoo email server: 

421+4.7.0+[TSS04] +Messages+from+50.56.156.88+temporarily+deferred +due+to+unexpected+volume+or+user+complaints+-+4.16.55.1;+see+https://postmaster.yahooinc.com/error-codes 0 0 170 0 125 SMTP 


Yahoo seems to be objecting to VOLUME as it's unlikely there are user complaints.

421 421 4.7.0 [TS01] Messages from x.x.x.x temporarily deferred due to user complaints – 4.16.55 We’re seeing unusual traffic patterns from your server.
421 421 4.7.0 [TS02] Messages from x.x.x.x temporarily deferred due to user complaints – 4.16.55 We’re seeing unusual traffic patterns from your server or your mailings are generating complaints from Yahoo Mail users.

https://glockapps.com/blog/remove-ip-address-yahoo-blacklist/


Emails from SupportSync may be flagged by Yahoo because of their format: 

The problem is that Yahoo's rules may not account for an operation like SupportSync, where we send out many emails of similar format (RMA notifications) that are actually legitimate and not SPAM.

We'll update this article as we work with Yahoo to fix this error. 


We verified our server is not on the following blacklists:

https://check.spamhaus.org/results?query=50.56.156.88

https://mxtoolbox.com/SuperTool.aspx?action=blacklist%3a50.56.156.88&run=toolpage

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