[horde] Unwanted folder in Horde

[fraser@intdatasys.co.uk]

Hope someone can help.

I've been using Horde for some time without any problems, after  
switching over from Neomail.  However recently, I noticed that a new  
mail folder had been created, and it seems to contain a load of spam.  
The folder is named '#ftp', and it contains a list of other folders,  
each with a different name, and each of contains one email apiece.   
All the emails appear to be from the same sender -  
ftp at earthdnsprotect.com.

I doon't know how this folder was created, but anyway, I cannot delete  
it from Horde as whenever I select the folder and attempt the Delete  
Folder(s) command, I get the message:

The folder "#ftp" was not deleted.  This is what the server said:  
DELETE failed: Can't delete mailbox #ftp: no such mailbox.

If I try and select the 'Empty folders' command on the #ftp folder, it  
give me the message:

The mailbox #ftp is already empty.

I have tried logging into the control panel of my webmail to delete  
the folder there, but it is not listed anywhere on the file directory.

Not sure how to go about deleting this folder - can anybody help?

Thanks,

Fraser.