Hello
Thank you for your question and reaching out.
I can understand you are having some issues accessing External website in Internal network.
Please try to fist Ping to the website xyz.com , if you are not able to ping then that would be an issue.
Maybe check any firewalls - possibly something updated & turned on a firewall (rule) that wasn't enabled previously?
Check AV, etc. The usual suspects.
Alternatively , Create a new internal zone called website.company.com. Then point an A record to your webserver. Then you would be able to get to the website using that address internally. Probably not the most elegant solution but it should work.
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