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+Cronjob will execute expired customer, this is important
+
+
+
+Run
+
+```bash
+crontab -e
+```
+
+this will run every 4 hours
+
+```bash
+0 */4 * * * /usr/bin/php -f /path/to/phpmixbill/system/cron.php
+```
+
+if you create hourly voucher, maybe you need to run every 5 minutes
+
+```bash
+*/5 * * * * /usr/bin/php -f /path/to/phpmixbill/system/cron.php
+```
+
+another example [crontab.guru](https://crontab.guru/examples.html)
+
+i dont know about windows, maybe using Scheduller, just search google
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