Site accessibility & firewall considerations (Error 404 or Load Failed)
Overview
Modern Excel add-ins cannot make a direct connection to your ERP system due to the browser engine restrictions for cross-origin requests. In Excel for Mac and Excel Desktop for Windows, MS Office utilizes a Safari or Edge-based browser engine behind the scenes.
Therefore, Velixo NX uses a secure proxy server to facilitate the connection to your ERP system. The proxy never caches or stores your ERP data, it is used solely for authentication and request pass-through.
However, the fact that such a proxy server exists has two important implications:
Any ERP site that you connect to must be accessible over the public internet, with no VPN requirement
If your ERP host uses a firewall, it is important to allow-list not just your end users' IP addresses, but also those of Velixo NX's proxy servers
IP ranges and addresses for allow-listing:
173.245.48.0/20
103.21.244.0/22
103.22.200.0/22
103.31.4.0/22
141.101.64.0/18
108.162.192.0/18
190.93.240.0/20
188.114.96.0/20
197.234.240.0/22
198.41.128.0/17
162.158.0.0/15
104.16.0.0/13
104.24.0.0/14
172.64.0.0/13
131.0.72.0/22
15.157.55.169
13.239.34.44Symptoms
If those IP ranges and addresses are not allowed, this can result in errors during the connection process, such as Error: "504" or Error: "Load Failed".
