After updating form the latest Kirby Version 2 to the newest Version 3 I now have just one last issue with my Panel in that I can’t access /panel/site
Return value of Kirby\Cms\Site::blueprint() must be an instance of Kirby\Cms\SiteBlueprint, null returned
Any Idea on how to fix that?
Hm, have you fiddled with anything inside the Kirby folder? E.g removed or renamed /kirby/config/blueprints/site.yml?
No, I just replaced the folder as advised in the How To. Just did that again (upload starterkit ZIP to server, extract archive, move Kirby Folder to correct place).
You mean you get the same error with a fresh Kirby 3 Starterkit? Or just when you move the Kirby folder into your old K2 installation?
No, I just replaced the Kirby Folder of V3 with the one in my V2 installation.
Ok, and have you followed the other instructions as well, like removing the K2 Panel folder, replacing the index.php and .htaccess, make the blueprints .yml files and put them into the right subfolders etc.?
The only way I can make Kirby throw your error is by removing the fallback file I mentioned above, hm 
Yes, done that…
Are you using any plugins that might interfere?
No. The /plugins and /fields folders are both empty.
Could you post your site.yml please?
Here you go!
/kirby/config/blueprints/site.yml
name: Site
title: Site
sections:
pages:
headline: Pages
type: pagesPlease remove the first line: name: site is not a property. The first line always has to be the title. Name didn’t exist in Kirby 2 either, where did you get that from?
…its in the /kirby/config/blueprints/site.yml from the starterkit-master.
But unfortunately it still shows the same error.
No, I meant your /site/blueprints/site.yml, don’t touch anything in the Kirby folder. You have to undo your changes in that file.
Ah, okay. Wasn’t sure because you asked about the one in the Kirby folder before. The /site/blueprints/site.yml looks like this:
title: Site
fields:
previewfiles:
type: previewfiles
title:
label: Titel
type: text
width: 1/2
copyright:
label: Copyright
type: text
width: 1/2
description:
label: SEO Beschreibung
type: markdown
time_cal:
label: Sprechzeiten und Urlaub
type: headline
numbered: false
urlaub:
label: Urlaub
type: structure
style: table
help: >
<b>Hinweis:</b> Sobald ein Datumsbereich hinterlegt ist wird der Urlaubsbanner auf der Website angezeigt. Dieser wird jedoch automatisch nur bis zum Ende des Urlaubs angezeigt.
entry:
- start
- end
fields:
start:
label: Beginn
type: date
format: DD.MM.YYYY
end:
label: Ende
type: date
format: DD.MM.YYYY
times:
label: Sprechzeiten (kompakt)
type: structure
style: table
help: >
Bitte beim ändern der Zeiten der kompakten Ansicht (Darstellung der Zeiten am Anfang und Ende der Seite) immer auch die Zeiten in der ausführlichen Ansicht (Berechnung der Öffnungszeiten - Bspw.: "Noch 2 Stunden erreichbar") ändern.
entry:
- day
- time
fields:
day:
label: Wochentag
type: text
help: Wochentage in Kurzform und getrennt durch Kommas (Mo, Di, Mi) angeben
time:
label: Zeiten
type: text
help: Uhrzeiten mit Doppelpunkt getrennt (12:00 - 18:00) angeben
hours:
label: Sprechzeiten (ausführlich)
type: structure
style: table
help: >
Bitte beim ändern der Zeiten in der ausführlichen Ansicht (Berechnung der Öffnungszeiten - Bspw.: "Noch 2 Stunden erreichbar") immer auch die Zeiten in der kompakten Ansicht (Darstellung der Zeiten am Anfang und Ende der Seite) ändern.
entry:
- tag
- von1
- bis1
- von2
- bis2
fields:
tag:
label: Wochentag
type: select
options:
Montag: Montag
Dienstag: Dienstag
Mittwoch: Mittwoch
Donnerstag: Donnerstag
Freitag: Freitag
Samstag: Samstag
Sonntag: Sonntag
von1:
label: Vormittags von
type: text
help: Uhrzeiten mit Punkt getrennt (08.00) angeben
validate:
match: "/\d\d.\d\d/"
bis1:
label: bis
type: text
help: Uhrzeiten mit Punkt getrennt (12.00) angeben
validate:
match: "/\d\d.\d\d/"
von2:
label: Nachmittags von
type: text
help: Uhrzeiten mit Punkt getrennt (14.00) angeben
validate:
match: "/\d\d.\d\d/"
bis2:
label: bis
type: text
help: Uhrzeiten mit Punkt getrennt (18.00) angeben
validate:
match: "/\d\d.\d\d/"
contact:
label: Anfahrtsbeschreibung und Kontaktdaten
type: headline
numbered: false
location:
label: Ort
type: markdown
opnv:
label: Anfahrt ÖPNV
type: structure
style: table
limit: 1
width: 1/2
entry:
- ffm
- of
fields:
ffm:
label: Von Frankfurt
type: markdown
of:
label: Von Offenbach
type: markdown
pkw:
label: Anfahrt PKW
width: 1/2
type: markdown
phone:
label: Telefonnummer
type: tel
width: 1/2
email:
label: E-Mail
type: email
width: 1/2
map:
label: Adresse
type: osmap
center:
lat: 50.099978262154295
lng: 8.724453761993345
zoom: 14
help: >
Ok, when I put that into a Kirby 3 Starterkit, it works, although there are some fields missing at my end the the structure field doesn’t have an entry option anymore.
I’m running out of ideas.
Have you made sure your server fulfils all requirements for Kirby 3?
If you want, you can send me your project as zip for testing on my end…
The only new requirement is PHP 7.1+ and I am running PHP 7.3. All other requirements (PHP extensions, APACHE 2) are met.
Would be great to finde a solution to that. How can I send the project zip to you?
You could upload it somewhere (Dropbox, google, WeTransfer…) and send me a download link via PM
The issue seems to be the last line (help: >), where help text is missing.
Ah! It works! Thank you very much.