000466 : <value> does not match the schema of target <value>.

Description

If Schema Type is set as TEST,schemas of input feature classes must match the schema of the target feature class.

Solution

Make sure all the input feature classes or tables have the same attribute schemas. If the schemas are not the same, you can set the Schema Type parameter to NO_TEST, so only those fields and their values within the input that match fields within the target dataset are used. See the Append tool documentation for a more detailed explanation.