Describes the cause and action for error messages.
Error Message(English)：
invalid variant operation
Invalid Variant Operation
https://stackoverflow.com/questions/27537952/invalid-variant-operation
Invalid Variant Operation when comparing an OleVariant to ...
https://stackoverflow.com/questions/18533890/invalid-variant-operation-when-comparing-an-olevariant-・・・
Invalid Variant Operation error
https://stackoverflow.com/questions/1279813/invalid-variant-operation-error
Invalid variant operation error
https://stackoverflow.com/questions/6890386/invalid-variant-operation-error
Excel and invalidvariant operation - delphi
http://www.delphigroups.info/2/3/933794.html
"Cannot Open xxx files"や"Invalid Variant operation"エラーを ... - Navicat
https://help.navicat.com/hc/ja/articles/218385387-xlsx%E3%83%95%E3%82%A1%E3%82%A4%E3%83%AB%E3%81%A8a・・・
インポートウィザード ? Navicat
https://help.navicat.com/hc/ja/sections/203990397-%E3%82%A4%E3%83%B3%E3%83%9D%E3%83%BC%E3%83%88%E3%8・・・
Frequently Asked Questions - Software
https://www.pcord.com/nichefaq.htm
OLEVariants problem - Lazarus forum - Free Pascal
https://forum.lazarus.freepascal.org/index.php?topic=44337.0