1. This is not from Git.
2. This appears to be a cpanel installation.  We can not support such 
installations since they may be heavily modified and are almost 
impossible to debug.

Does that mean you are a user, i.e. not the administrator of this system?

When I go to the email program now, and click on "folders", I still 
can not see the folders on the left, but I can see my folders in the 
view on the right.
But only below the following error report ;

QUOTE BEGINS

Notice: Undefined index: INBOX.1) Tuna Cafe - website Tuna.Maori in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 691

Notice: Undefined index: c in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 724

Notice: Undefined index: p in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 725

Notice: Undefined index: v in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 726

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1328

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1275

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1438

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/imp/lib/IMAP/Tree.php on line 442

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1225

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/imp/lib/IMAP/Tree.php on line 442

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/imp/lib/IMAP/Tree.php on line 442

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1328

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1099

Notice: Undefined index: v in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1107

Notice: Undefined index: INBOX.1) Tuna Cafe - website Tuna.Maori in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 691

Notice: Undefined index: c in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 724

Notice: Undefined index: p in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 725

Notice: Undefined index: v in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 726

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1328

Notice: Undefined index: a in 
/usr/local/cpanel/base/horde/lib/Horde/IMAP/Tree.php on line 1225

QUOTE ENDS

Problem;
The folders view on left side has disappeared.

Events leading up to the problem;
1) Erroneous creation of sub-folder
I created a folder, and used "." in the name (because it was a folder 
about a website).
When I clicked to create the folder, instead of making the single 
folder called (say) "blahblah.de.blah" (without quotes), it made a 
folder called "blahblah" (wq) which had a sub-folder called "de" (wq), 
which had a sub-folder "blah" (wq).
2) This was not what I wanted (though I had been wondering how to 
create sub-folders [itself a task that either doesn't work intuitively 
or it doesn't work]).
  So I ticked/checked the box for the main "blahblah" (wq) folder, 
which I assumed would include the subfolders (and may expect a warning 
message "about to delete a sub-folder[s]").
Then I deleted the main "blahblah" folder, but instead of it getting 
deleted, the webmail made a second Duplicate folder (also with the 
sub-folders).
I then refreshed the view in the browser, to make sure that I was 
viewing the truth of the matter.
Yes there were two folders exactly the same , with exactly the same 
sub-folders.
So I then checked both the folders AND their sub-folders, and deleted them.
Then my complete view of the folders on the left side of web-mail view 
Disappeared.

I am unable to tell whether ;
a) I have lost "view" of the folders
b) I have lost the folders
c) I have lost view of the contents of the folders
d) I have lost the contents of the folders

Thank you for any help you can give in resolving this matter.

Asside;
When starting to make this bug submission,
the user gets presented with a long list of options.
The list has the names of the Horde packages, with an explanation of 
what they are in brackets after.
The "names" of the packages mean nothing to the user, they only know 
"what" they were doing.

So please consider re-formulating the question along the line of -
"What were you doing when you had problem(s)?"
choose from list of actions (with package name in brackets).

And in any case, because the list is actually "Two" lists, it would be 
more clearly displayed,
if the second list was positioned to be located in a consisted 
"column" distance from the left.


ALSO Opportunities
I remember when you guys started up back before 2001,
good to see you continuing well.
Opportunities ;
a) Have you considered making interfaces/plugins that work with other 
Groupware programs, and CMS systems (e.g. Joomla)?
b) Have you got easy import/export or synchronisation features to be 
compatible with common email programs and office suites?

c) Bug Reports
To "capture" events more easily (and these could be at the early 
"symptom" stage, rather than the eventual "disaster" stage), please 
consider having a link included in the menu  at the top of the page 
view, to "report a bug", and also "report a bug from/related to this 
page".
And for those who have suffered a problem that makes horde no longer 
functional, it would be handy to have a link that could be provided in 
their web space management system (which is not Horde - but is used to 
manage their horde system as a web space integrated system).
That way, the Horde team is far more likely to hear about the kind of 
problems that they would otherwise not be able to hear about, because 
the user has had their communications system (horde) damaged to the 
point of un-workable.

It would also be handy if those bug report links could be 
pre-configured to include the email address of the sender, in case 
they are filling in the bug report form in a situation where their 
email system won't work.

It would also be helpful to capture the information of the domain of 
their Horde hoster (either manually or from the email address), so 
that any issues related to the problem and the hoster's system can be 
liaised about.

LASTLY
sorry about the bunch of ideas included in this bug report,
but I really didn't want to have to go through the same process over 
and again.
So I hope you can find some way to handle these.

Yours
Alasdair