MySQL suddenly doesn't start: no errors in logfile

[sarefo]

I had a nicely running Apache/MariaDB install running the last few days. After I just updated Windows 11 to the newest version, "MySQL" starts and stops:

7:55:11 PM [mysql] Attempting to start MySQL app...
7:55:12 PM [mysql] Status change detected: running
7:55:14 PM [mysql] Status change detected: stopped
7:55:14 PM [mysql] Error: MySQL shutdown unexpectedly.
7:55:14 PM [mysql] This may be due to a blocked port, missing dependencies,
7:55:14 PM [mysql] improper privileges, a crash, or a shutdown by another method.
7:55:14 PM [mysql] Press the Logs button to view error logs and check
7:55:14 PM [mysql] the Windows Event Viewer for more clues
7:55:14 PM [mysql] If you need more help, copy and post this
7:55:14 PM [mysql] entire log window on the forums

I checked the mysql_error.log file, and the output seems perfectly fine to me:

2024-03-02 19:55:12 0 [Note] Starting MariaDB 10.4.32-MariaDB source revision c4143f909528e3fab0677a28631d10389354c491 as process 7080
2024-03-02 19:55:12 0 [Note] InnoDB: Mutexes and rw_locks use Windows interlocked functions
2024-03-02 19:55:12 0 [Note] InnoDB: Uses event mutexes
2024-03-02 19:55:12 0 [Note] InnoDB: Compressed tables use zlib 1.3
2024-03-02 19:55:12 0 [Note] InnoDB: Number of pools: 1
2024-03-02 19:55:12 0 [Note] InnoDB: Using SSE2 crc32 instructions
2024-03-02 19:55:12 0 [Note] InnoDB: Initializing buffer pool, total size = 16M, instances = 1, chunk size = 16M
2024-03-02 19:55:12 0 [Note] InnoDB: Completed initialization of buffer pool
2024-03-02 19:55:12 0 [Note] InnoDB: 128 out of 128 rollback segments are active.
2024-03-02 19:55:12 0 [Note] InnoDB: Creating shared tablespace for temporary tables
2024-03-02 19:55:12 0 [Note] InnoDB: Setting file 'C:\xampp\mysql\data\ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...
2024-03-02 19:55:12 0 [Note] InnoDB: File 'C:\xampp\mysql\data\ibtmp1' size is now 12 MB.
2024-03-02 19:55:12 0 [Note] InnoDB: Waiting for purge to start
2024-03-02 19:55:12 0 [Note] InnoDB: 10.4.32 started; log sequence number 67971925; transaction id 56839
2024-03-02 19:55:12 0 [Note] InnoDB: Loading buffer pool(s) from C:\xampp\mysql\data\ib_buffer_pool
2024-03-02 19:55:12 0 [Note] Plugin 'FEEDBACK' is disabled.
2024-03-02 19:55:12 0 [Note] InnoDB: Buffer pool(s) load completed at 240302 19:55:12
2024-03-02 19:55:12 0 [Note] Server socket created on IP: '::'.

so, how would I proceed from here? many thanks for any help

UPDATE: Without any apparent change, now MySQL displays as green in the XAMPP control panel, but the Mediawiki that depends on it loads indefinitely in the browser without any data coming through…

[sarefo]

I found this in the Windows Event Viewer, but can't make sense of it:

> Fatal error: Can't open and lock privilege tables: Incorrect file format 'db'
> Aborting
> mysqld.exe: Error writing file 'C:\xampp\mysql\data\aria_log_control' (Errcode: 9 "Bad file descriptor")
> mysqld.exe: Aria engine: checkpoint failed
> mysqld.exe: Error writing file 'C:\xampp\mysql\data\aria_log_control' (Errcode: 9 "Bad file descriptor")

As I said, the thing worked flawlessly since the install a few days ago. Just after the newest Windows upgrade it's acting up like this.

[sarefo]

by the way, I tried restoring from the backup as outlined in this short video linked in another thread, that didn't work: https://www.youtube.com/watch?v=84IOtc05TuA&t=8s

[sarefo]

so I removed xampp, re-installed it, and kept moving files from the old install till it broke again. Here's what I found: mysql runs fine. there are not so many files in the xampp/mysql/data/mysql folder that were touched since the install. when I copy most of them over from the backup of the old install to the new one, mysql still starts fine. but when I copy those two files from the old into the new, mysql won't start anymore: innodb_index_stats.ibd / innodb_table_stats.ibd.

so I guess my question would be: is there any way to fix these two? or am I on the wrong track here?