Liberum Helpdesk error message updating/closing problems

[El_Nombre]

I'm pretty unfamiliar with the software itself. My predecessor here has left and I am in charge of the day-to-day running of the network. It's been a huge learning curve and I've come unstuck on a few occasions, but managed to pull it together.

This one, however, has stumped me.

Helpdesk has worked without a hiccup in over two years but now it's answering me back. When trying to close or update a problem, which should send an email to the user who submitted the problem, the following message appears:

Application Error
Number: 5 (0x00000005)
Source: Persits.MailSender.4
Description: Software caused connect abort.
--------------------------------------------------------------------------------
No more information is available.
Contact your administrator or visit the Liberum Help Desk website.

I have no idea what to do or where to look to fix this. I've visited the Liberum website and my Google-fu is too weak to turn up any answers.

Anyone have any ideas where to start? Thanks in advance for reading.

[El_Nombre]

Gah - a colleague fixed the pesty thingy.

The IP address of the server Helpdesk lives on wasn't in the SMTP list of the Exchange server anymore. I think the LEA must have done that by accident.

Back in, all better - so a return to all those lovely helpdesk cases.