jQuery Error on submitting the form

Hi!

I built a form with several file uploads.

When I submit the forms without any file upload it works. If there are files attached, the black wheel keeps spinning and it shows me the following error in the console:

Uncaught TypeError: Cannot read property 'dispatchEvent' of undefined
    at Object.wpcf7.triggerEvent (scripts.js?ver=5.1.7:367)
    at ajaxSuccess (scripts.js?ver=5.1.7:257)
    at Object.<anonymous> (scripts.js?ver=5.1.7:350)
    at i (jquery.js?ver=1.12.4-wp:2)
    at Object.fireWith [as resolveWith] (jquery.js?ver=1.12.4-wp:2)
    at x (jquery.js?ver=1.12.4-wp:4)
    at XMLHttpRequest.c (jquery.js?ver=1.12.4-wp:4)
wpcf7.triggerEvent @ scripts.js?ver=5.1.7:367
ajaxSuccess @ scripts.js?ver=5.1.7:257
(anonymous) @ scripts.js?ver=5.1.7:350
i @ jquery.js?ver=1.12.4-wp:2
fireWith @ jquery.js?ver=1.12.4-wp:2
x @ jquery.js?ver=1.12.4-wp:4
c @ jquery.js?ver=1.12.4-wp:4
XMLHttpRequest.send (async)
send @ jquery.js?ver=1.12.4-wp:4
ajax @ jquery.js?ver=1.12.4-wp:4
wpcf7.submit @ scripts.js?ver=5.1.7:341
(anonymous) @ scripts.js?ver=5.1.7:56
dispatch @ jquery.js?ver=1.12.4-wp:3
r.handle @ jquery.js?ver=1.12.4-wp:3

I guess this is some sort of JS conflict. I cannot just try to switch everything else off as this is a live site of a company. Even if I knew the theme or any other plugin is the problem, I would be interessted in solving this issue. I googled a lot but I still do not really understand whats the problem.

Thanks!

• This topic was modified 6 years, 1 month ago by brainzina.

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