The server's certificate is unknown

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Ninno
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The server's certificate is unknown

#1 Post by Ninno » 2020-05-05 08:39

Hello,
I took a certificate for my server from the Let's Encrypt authority and uploaded it to my Filezilla server.
But when I connect to the server through my filezilla client, I still receive a certificate unknown error, and I have to manually accept it with a valid certificate by selecting the appropriate flag. (see attach)

The hostname is the same and I have also activated the reverse on the public ip, how can I avoid this message?

Thanks
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domanda.png
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botg
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Re: The server's certificate is unknown

#2 Post by botg » 2020-05-05 09:43

Yes, FileZilla uses user-guided Trust On First Use (TOFU). You need to compare the displayed fingerprint with the actual fingerprint you have received from the server administrator through a different, secure channel. It's just like with SSH host keys, same principle.

xtian
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Re: The server's certificate is unknown

#3 Post by xtian » 2020-05-31 14:25

I get the same problem but the trust the certificate boxes are greyed out??
Only just started happening

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boco
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Re: The server's certificate is unknown

#4 Post by boco » 2020-05-31 16:07

Just a wild guess: The certificate (or any other in the chain) is expired. Expired or invalid certificates cannot be trusted permanently.
### BEGIN SIGNATURE BLOCK ###
No support requests per PM! You will NOT get any reply!!!
FTP connection problems? Do yourself a favor and read Network Configuration.
FileZilla connection test: https://filezilla-project.org/conntest.php
### END SIGNATURE BLOCK ###

janejewett
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Re: The server's certificate is unknown

#5 Post by janejewett » 2020-06-03 14:16

I always get the pop-up that the certificate is unknown and I don't mind manually overriding that in the pop-up -- but just in the last couple of days the pop-up is cut off at the bottom so the option to trust this certificate doesn't show, and I can't move the dialog box up to show that option. I'm stuck. How to manually override if I can't access the override option?

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boco
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Re: The server's certificate is unknown

#6 Post by boco » 2020-06-03 15:15

What is your screen resolution? Would you mind a screenshot?

The certificate dialog in FileZilla Client has been redesigned recently, there might still be some rough edges. Press the tab key one, two or three times*, then Space (or Return). I have to do that on my netbook (1024 x 600 resolution), too.

*How often you have to press TAB depends on the situation:

Both checkboxes greyed out: 1x
"Trust checkbox" active: 2x
"Trust checkbox" and "Trust alternative hostnames" box active: 3x

For example, the OP would need to press TAB three times, as both checkboxes are active.
### BEGIN SIGNATURE BLOCK ###
No support requests per PM! You will NOT get any reply!!!
FTP connection problems? Do yourself a favor and read Network Configuration.
FileZilla connection test: https://filezilla-project.org/conntest.php
### END SIGNATURE BLOCK ###

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botg
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Re: The server's certificate is unknown

#7 Post by botg » 2020-06-03 21:42

On Windows you could as workaround also do Alt+Space and then select move and move the window upwards until the buttons come into view.

EssKayInVA
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Re: The server's certificate is unknown

#8 Post by EssKayInVA » 2020-07-29 20:23

I am moving a site to another ISP and have also encountered this issue in FZ v3.49.1 re Unknown Certificate dialog and the grayed out checkboxes for Trust This Certificate. My screen resolution of 1920x1200 is large enough to display the entire dialog.

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botg
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Re: The server's certificate is unknown

#9 Post by botg » 2020-07-30 13:31

If the checkboxes are greyed out something is wrong with the certificate and the certificate needs to be replaced.

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