After the site is migrated to HTTPS, ^null$-errors are displayed in Logwatch (the connection is closed until the server receives a response) for all hosts that access the site.

How can I remove this error?

In the Logwatch email report:

```
*.** MB transferred in 7645 responses (1xx 7645, 2xx 0, 3xx 0, 4xx 0, 5xx 0)
...
^null$ 2359 Time(s)
...

```