LDAP issues where the LDAP Server return multiple values for one attribute

I got the following error message when i try to configure LDAP authentication.

I use the latest version.
Any Ideas ?

And by the way i can't change the LDAP layout.

Hi @timmel
Please post "Diagnostic Info" from Admin > Troubleshooting.
What do you mean by "can't change the LDAP layout" ?

{
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"java.vm.version": "11.0.11+9",
"os.name": "Linux",
"os.version": "5.4.0-74-generic",
"user.language": "en",
"user.timezone": "GMT"
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"metabase-info": {
"databases": [
"h2",
"mysql"
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"hosting-env": "unknown",
"application-database": "h2",
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"database": {
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"jdbc-driver": {
"name": "H2 JDBC Driver",
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"run-mode": "prod",
"version": {
"date": "2021-05-27",
"tag": "v0.39.3",
"branch": "release-x.39.x",
"hash": "598a112"
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LDAP layout -> LDAP schema

@timmel Metabase requires that you return a single string in firstname, lastname and email.
Latest release is 0.39.4

@timmel You can set base search and attribute in the configuration:
https://www.metabase.com/docs/latest/administration-guide/10-single-sign-on.html#enabling-ldap-authentication

ok let me look for other LDAP attributes in the schema

I found other attributes and now it works.
Thanks for your time !