diff --git a/src/main/frontend/components/administration/ConfigFormField.tsx b/src/main/frontend/components/administration/ConfigFormField.tsx
index d9d44f5..7cce99d 100644
--- a/src/main/frontend/components/administration/ConfigFormField.tsx
+++ b/src/main/frontend/components/administration/ConfigFormField.tsx
@@ -2,9 +2,18 @@ import ConfigEntryDto from "Frontend/generated/de/grimsi/gameyfin/config/dto/Con
 import React from "react";
 import Input from "Frontend/components/general/Input";
 import CheckboxInput from "Frontend/components/general/CheckboxInput";
+import SelectInput from "Frontend/components/general/SelectInput";
 
 export default function ConfigFormField({configElement, ...props}: any) {
     function inputElement(configElement: ConfigEntryDto) {
+
+        if (configElement.allowedValues != null && configElement.allowedValues.length > 0) {
+            return (
+                <SelectInput label={configElement.description} name={configElement.key}
+                             values={configElement.allowedValues} {...props}/>
+            );
+        }
+
         switch (configElement.type) {
             case "Boolean":
                 return (
diff --git a/src/main/frontend/components/administration/SsoManagement.tsx b/src/main/frontend/components/administration/SsoManagement.tsx
index 7d5935a..38c63e4 100644
--- a/src/main/frontend/components/administration/SsoManagement.tsx
+++ b/src/main/frontend/components/administration/SsoManagement.tsx
@@ -74,6 +74,38 @@ function SsoMangementLayout({getConfig, formik}: any) {
     );
 }
 
-const validationSchema = Yup.object({});
+const validationSchema = Yup.object({
+    sso: Yup.object({
+        oidc: Yup.object({
+            enabled: Yup.boolean(),
+            "auto-register-new-users": Yup.boolean().required(),
+            "match-existing-users-by": Yup.string().required(),
+            "client-id": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("Client ID is required") : schema
+            ),
+            "client-secret": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("Client Secret is required") : schema
+            ),
+            "issuer-url": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("Issuer URL is required") : schema
+            ),
+            "authorize-url": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("Authorize URL is required") : schema
+            ),
+            "token-url": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("Token URL is required") : schema
+            ),
+            "userinfo-url": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("Userinfo URL is required") : schema
+            ),
+            "logout-url": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("Logout URL is required") : schema
+            ),
+            "jwks-url": Yup.string().when("enabled", ([enabled], schema) =>
+                enabled ? schema.required("JWKS URL is required") : schema
+            )
+        })
+    })
+});
 
 export const SsoManagement = withConfigPage(SsoMangementLayout, "Single Sign-On", "sso", validationSchema);
\ No newline at end of file
diff --git a/src/main/frontend/components/general/SelectInput.tsx b/src/main/frontend/components/general/SelectInput.tsx
new file mode 100644
index 0000000..f97a398
--- /dev/null
+++ b/src/main/frontend/components/general/SelectInput.tsx
@@ -0,0 +1,28 @@
+import {useField} from "formik";
+import {Select, SelectItem} from "@nextui-org/react";
+
+// @ts-ignore
+const SelectInput = ({label, values, ...props}) => {
+    // @ts-ignore
+    const [field] = useField(props);
+
+    return (
+        <div className="flex flex-row flex-1 items-center gap-2 my-2">
+            <Select
+                {...field}
+                {...props}
+                id={field.name}
+                label={label}
+                defaultSelectedKeys={[field.value]}
+            >
+                {values.map((value: string) => (
+                    <SelectItem key={value} value={value}>
+                        {value.toLowerCase()}
+                    </SelectItem>
+                ))}
+            </Select>
+        </div>
+    );
+}
+
+export default SelectInput;
\ No newline at end of file
diff --git a/src/main/kotlin/de/grimsi/gameyfin/config/ConfigProperties.kt b/src/main/kotlin/de/grimsi/gameyfin/config/ConfigProperties.kt
index 863dcc6..d32bbf3 100644
--- a/src/main/kotlin/de/grimsi/gameyfin/config/ConfigProperties.kt
+++ b/src/main/kotlin/de/grimsi/gameyfin/config/ConfigProperties.kt
@@ -7,7 +7,8 @@ sealed class ConfigProperties<T : Serializable>(
     val type: KClass<T>,
     val key: String,
     val description: String,
-    val default: T? = null
+    val default: T? = null,
+    val allowedValues: List<T>? = null
 ) {
 
     /** Libraries */
@@ -114,7 +115,8 @@ sealed class ConfigProperties<T : Serializable>(
         MatchUsersBy::class,
         "sso.oidc.match-existing-users-by",
         "Match existing users by",
-        MatchUsersBy.USERNAME
+        MatchUsersBy.USERNAME,
+        MatchUsersBy.entries
     )
 
     data object SsoAutoRegisterNewUsers : ConfigProperties<Boolean>(
diff --git a/src/main/kotlin/de/grimsi/gameyfin/config/ConfigService.kt b/src/main/kotlin/de/grimsi/gameyfin/config/ConfigService.kt
index e3b3234..dbe6513 100644
--- a/src/main/kotlin/de/grimsi/gameyfin/config/ConfigService.kt
+++ b/src/main/kotlin/de/grimsi/gameyfin/config/ConfigService.kt
@@ -40,7 +40,8 @@ class ConfigService(
                 value = appConfig?.value ?: configProperty.default?.toString(),
                 defaultValue = configProperty.default?.toString(),
                 type = configProperty.type.simpleName ?: "Unknown",
-                description = configProperty.description
+                description = configProperty.description,
+                allowedValues = configProperty.allowedValues?.map { it.toString() }
             )
         }
     }
@@ -172,9 +173,14 @@ class ConfigService(
             Boolean::class -> value.toBoolean() as T
             Int::class -> value.toFloat().toInt() as T
             Float::class -> value.toFloat() as T
-            Enum::class -> value as T
             else -> {
-                throw RuntimeException("Unknown config type ${configProperty.type}: '$value' for key ${configProperty.key}")
+                if (configProperty.type.java.isEnum) {
+                    val enumConstants = configProperty.type.java.enumConstants
+                    enumConstants.firstOrNull { it.toString() == value }
+                        ?: throw IllegalArgumentException("Unknown enum value '$value' for key ${configProperty.key}")
+                } else {
+                    throw IllegalArgumentException("Unknown config type ${configProperty.type}: '$value' for key ${configProperty.key}")
+                }
             }
         }
     }
diff --git a/src/main/kotlin/de/grimsi/gameyfin/config/dto/ConfigEntryDto.kt b/src/main/kotlin/de/grimsi/gameyfin/config/dto/ConfigEntryDto.kt
index fcb45b4..9bfe4da 100644
--- a/src/main/kotlin/de/grimsi/gameyfin/config/dto/ConfigEntryDto.kt
+++ b/src/main/kotlin/de/grimsi/gameyfin/config/dto/ConfigEntryDto.kt
@@ -9,5 +9,6 @@ data class ConfigEntryDto(
     val value: String?,
     val defaultValue: String?,
     @field:Nonnull val type: String,
-    @field:Nonnull val description: String
+    @field:Nonnull val description: String,
+    val allowedValues: List<String>?
 )
\ No newline at end of file