有没有理由在点击按钮后加载文件浏览器这么久?

Guys I work at website in PHP and in the registration form we have simple photouploader for only one photo. On my computers (Windows 10 + Microsoft Edge and chrome) and Macbook Pro (newest os and safari and chrome) everything works fine and after Click on "upload" button I can see the file browser. But at PCs of my client (2x Windows 7 + Google chrome) after Click on the button, nothing happened and Google Chrome got freezed. After 5minutes the file browser opened, when I close him and again Click on the button, he showed up in 3s. After restarting the Chrome or PC, the same problem is there. If I go through Internet Explorer on one of the client PCs the file browser is showing up fast. There is just problem with the chrome. Also, my client have a lot network directories.

I tried it on several computers and browsers, but probably, there is just problem with Windows 7 and Chrome combination or maybe there is problem with a lot of network directories on her computer.

Did somebody face that kind of problem?