1. Add the following line in /etc/postfix/main.cf . All outgoing emails will have this address in the FROM field, but the name of the sender will not be modified. Replace <FQDN> with your fully qualified domain name.
```
sender_canonical_maps = static:no-reply@<FQDN>
```
2. To modify the name as well, you need to create a file in /etc/postfix/header_checks which contains this line:
```
/^From:[[:space:]]+(.*)/ REPLACE From: "Your Name" <email@company.com>
```
3. Then run the following commands:
```
cd /etc/postfix
postmap header_checks
postconf -e 'smtp_header_checks = regexp:/etc/postfix/header_checks'
service postfix reload
```