I had the problem that since I had activated ModSecurity, my Nextcloud instance no longer worked.
A lot of searching on the internet did not find a solution. Also the deactivation of various rules in Mod Security was only of moderate success.
Until I finally found the right solution.
One must in the file
re-enable an uncommented paragraph. This is specifically to make WebDAV run with ModSecurity.
**# Example: for WebDAV, add the following methods: CHECKOUT COPY DELETE LOCK
setvar:‘tx.allowed_methods=GET HEAD POST OPTIONS CHECKOUT COPY DELETE LOCK MERGE MKACTIVITY MKCOL MOVE PROPFIND PROPPATCH PUT UNLOCK REPORT SEARCH’”
and it will work.
I found it there: mod_security Anpassungen für Nextcloud LBM Services - Web-Development