Mozilla Thunderbird: How to create a link to a folder on a local network?

Question

Mozilla Thunderbird

Good afternoon. Installed for all users of the Thunderbird local network. A link to a file that is on a shared drive is sent without problems.
And here is a link to a directory (folder) of the following form: "U:\User\Folder\name" comes in the form:

<U:%5C%D0%9F%D0%BE%D0%BB%D1%8C%D0%B7%D0%BE%D0%B2%D0%B0%D1%82%D0%B5%D0%BB%D1%8C%5C%D0%9F%D0%B0%D0%BF%D0%BA%D0%B0%5C%D0%BD%D0%B0%D0%B7%D0%B2%D0%B0%D0%BD%D0%B8%D0%B5>

And, of course, there is no way to open it. Is there any solution for this issue?