Have had this error now for last two versions (1.06 and 1.07) after an initial successful use on 1.05.
Advanced IMAP is enabled (and works for Offline when enabled!) but currently Backup won't even start.

I started off recommending this program to Gmail users, but now find myself unable to use it. :-(
~~~~~~~~~~~
Error: Error occured, full traceback is bellow (gmb.py revision 691)
Traceback (most recent call last):
File "gmail-backup-gui.py", line 109, in _runThread
File "gmb.pyo", line 1218, in backup
File "gmb.pyo", line 630, in connect
File "gmb.pyo", line 617, in guessLanguage
ValueError: Cannot access IMAP folders


Traceback (most recent call last):
File "gmail-backup-gui.py", line 109, in _runThread
File "gmb.pyo", line 1218, in backup
File "gmb.pyo", line 630, in connect
File "gmb.pyo", line 617, in guessLanguage
ValueError: Cannot access IMAP folders


Just downloaded the latest version.
Every thing works just fine. I get all mails in my Outlook, an ofcourse in the webmail.
Outlook connects through IMAP, so I don't see this as the issue.

Any Ideas?

Btw. I'm using the app on a google apps account

I had the same error and JohnW's solution works fine !

Only put "show on imap" to "all mail" label on gmail set up and works fine !

Thankkkk u !!!!

Hi JohnW
I followed your way but can not resolve this. I try to do it several times but it still have the problem. How can I solve it, every ones?

GMail Backup revision 691 (2009-02-20)
Starting backup of account tuantab@gmail.com into E:\Tuan's Document\Gmail-tuantel backup 22-Jun-11
Error: Your Gmail account doesn't export some IMAP needed to Gmail Backup work.
Possible causes are:
- You are using the Gmail Labs.
Please go to the Settings/Label page and enable the IMAP access into
All Mails and Trash folders.
- You are using unsupported language of Gmail. Please run the following
command:

gmail-backup.exe list

and send the output of this command at info@gmail-backup.com.
Thank you
Error: Error occured, full traceback is bellow (gmb.py revision 691)
Traceback (most recent call last):
File "gmail-backup-gui.py", line 109, in _runThread
File "gmb.pyo", line 1218, in backup
File "gmb.pyo", line 630, in connect
File "gmb.pyo", line 617, in guessLanguage
ValueError: Cannot access IMAP folders

GMail Backup revision 691 (2009-02-20)
Starting backup of account tuantab@gmail.com into E:\Tuan's Document\Gmail-tuantel backup 22-Jun-11
Error: Your Gmail account doesn't export some IMAP needed to Gmail Backup work.
Possible causes are:
- You are using the Gmail Labs.
Please go to the Settings/Label page and enable the IMAP access into
All Mails and Trash folders.
- You are using unsupported language of Gmail. Please run the following
command:

gmail-backup.exe list

and send the output of this command at info@gmail-backup.com.
Thank you
Error: Error occured, full traceback is bellow (gmb.py revision 691)
Traceback (most recent call last):
File "gmail-backup-gui.py", line 109, in _runThread
File "gmb.pyo", line 1218, in backup
File "gmb.pyo", line 630, in connect
File "gmb.pyo", line 617, in guessLanguage
ValueError: Cannot access IMAP folders

You are using the latest version of GMail Backup.
GMail Backup revision 691 (2009-02-20)
Starting backup of account tuantab@gmail.com into E:\Tuan's Document\Gmail-tuantel backup 22-Jun-11
Error: Your Gmail account doesn't export some IMAP needed to Gmail Backup work.
Possible causes are:
- You are using the Gmail Labs.
Please go to the Settings/Label page and enable the IMAP access into
All Mails and Trash folders.
- You are using unsupported language of Gmail. Please run the following
command:

gmail-backup.exe list

and send the output of this command at info@gmail-backup.com.
Thank you
Error: Error occured, full traceback is bellow (gmb.py revision 691)
Traceback (most recent call last):
File "gmail-backup-gui.py", line 109, in _runThread
File "gmb.pyo", line 1218, in backup
File "gmb.pyo", line 630, in connect
File "gmb.pyo", line 617, in guessLanguage
ValueError: Cannot access IMAP folders

Hello, I have just installed the last version of Gmail-backup. The software does not start, indeed a pop-up message says: "See the logfile... for details". The message on the logfile is:

Traceback (most recent call last):
File "gmail-backup-gui.py", line 603, in
File "gmail-backup-gui.py", line 586, in __init__
File "gmail-backup-gui.py", line 273, in __init__
File "gmail-backup-gui.py", line 363, in restoreSettings
File "gmail-backup-gui.py", line 335, in settingsFn
File "os.pyo", line 435, in __getitem__
KeyError: 'APPDATA'

Can someone help me? Thanks in advance,

Maurizio

Error: Error occured, full traceback is bellow (gmb.py revision 691)
Traceback (most recent call last):
File "gmail-backup-gui.py", line 109, in _runThread
File "gmb.pyo", line 1218, in backup
File "gmb.pyo", line 630, in connect
File "gmb.pyo", line 617, in guessLanguage
ValueError: Cannot access IMAP folders

Thanks JohnW. By activating "Show in IMAP" all labels, the backup worked. For those with the same problem, try JohnW's solution.