reinstallation failed

You are welcome,

Please could you tell us your website address?

And also, perhaps, the reason you attempt to re-install WordPress?
and what all you did before browsing to wp-admin/install.php ?

You need to look at your wp-config.php file at line 22 and see what’s there, as that’s where the error is. Be aware that depending on the error it may be on the line above, but that doesn’t happen quite so often. Most times it’s because you’ve left out a quote or something very similar.

L could go one step further now. It was in fact a sign like ” ‘ “. But now I cannot log in. I get these messages:
?
Warning: Cannot modify header information – headers already sent by (output started at /kunden/314926_8001/web/1244574/A1244574/fkwb.ch/wp-config.php:1) in /kunden/314926_8001/web/1244574/A1244574/fkwb.ch/wp-login.php on line 425

Warning: Cannot modify header information – headers already sent by (output started at /kunden/314926_8001/web/1244574/A1244574/fkwb.ch/wp-config.php:1) in /kunden/314926_8001/web/1244574/A1244574/fkwb.ch/wp-login.php on line 438

I reinstalled because I moved from a testserver to the real address. No I have different passwords….

That error means that there’s a rouge space (or some other content) right at the start of yoru wp-config.php file. Remove that and it will be OK.

Be aware that some text editors can add in their own invisible characters before anything else, so if you can’t see anythng there, try another purely text editor or a good IDE and see if anything else shows up. For good practice, just do a couple of backspaces right before the opening <?php tag – just in case.