I read a thread with people discussing serious issues but i think they must have been talking about Plesk 6? Plesk 7 supports MailEnable Pro.
I had no problems installing with Plesk 7. Yes installed over the standard version which Plesk installed.
Then there are a few changes you need to make to get MailEnable Webmail working on webmail.domain.com instead of Horde.
1. go to Computer Management -> Local Users and Groups
2. set password to user account IME_USER
3. go to IIS Manager
4. select site "webmail(default)"
5. open "webmail(default)" Properties dialog
6. go to tab Home Directory and set it to <MailEnable Path>\Bin\WebMail
7. go to tab Directory Security and set IME_USER as anonymous
8. create MEWebMail virtual directory for folder <MailEnable
Path>\Bin\WebMail under "webmail(default)"
if you want to logon as user/password (by default you must logon as
user@domain/password), you should replace line 133:
oLogin.UserName = Request("UserID")
in <MailEnable Path>\Bin\WebMail\base\default\lang\EN\login.asp with
UserID = Request("UserID")
If InStr(1,UserID,"@") = 0 Then
' user & hostname
SiteName = GetSiteName()
If InStr(1,LCase(SiteName),"webmail.") = 1 Then
UserID = UserID & "@" &
Right(SiteName,Len(SiteName)-Len("webmail."))
End If
End If
oLogin.UserName = UserID