Any chance to start WoW-client without entering a password?

[nodoze]

Will a third party program affect WoW? I don't really understand the third program yet. It confused me. But if possible, please share more information with me. I'm ready to read them.
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I may be misunderstanding the context of the question/usage of the term "3rd Party Program" & affecting WoW... Your question is too vague... There are a myriad of 3rd Party Programs that can affect WoW and they can affect WoW in a myriad of ways...

The following are some examples of 3rd Party Programs (3PPs) that affect WoW from various perspectives:

https://wowopenbox.org/ (aka WOB)
https://www.joemultiboxer.com/ (aka JMB)
https://level-buddy.com/wow_switcher/
https://www.makeuseof.com/tag/a-begi...-command-line/
https://learn.microsoft.com/en-us/wi...oys/fancyzones
https://isboxer.com/
... (Note: There are many more 3PPs that can affect Wow... The above are just the most common examples that come to mind...);

You are encouraged to use the above links to read/study about any/all of those. Feel free to follow-up with more specific questions...