How to filter users with empty profile field?

You need to remove the single quotes around $profile_value when passing to UrlEncoding.  Also make sure the profile field is searchable.

I had tried this also but it didn't work. Can you suggest any other method to filter users where any specific profile field is empty?

Can you try the following?

#set($filters = '')
#set($query = "-profile_Occupation:*")
#set ($searchQuery1= "%{ Sort = 'date desc' }")
$searchQuery1.Add("Query", $query)
$searchQuery1.Add("Filters", "type::user${filters}")
$searchQuery1.Add("PageSize", "1000")
#set ($searchResults1 = $core_v2_searchResult.List($searchQuery1))

Thanks for help. It is really useful for me.

Thanks for help. It is really useful for me.