Where can I download a copy of MicrosoftWebForms ver 18.104.22.168? I can't import a managed solution without importing MicrosoftWebForms solution to the environment.
You can't install this solution manually. This is a part of Dynamcis 365 Portal Add on and installed when you enable the Portal addon. So if you need this, you need to enable the Dynamics 365 Portal Add On.
Hope this helps.
If you need more help that how to configure CRM portal add on then go to below link:
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