No mails, can someone please help me. I don't know what to do anymore

[jeronimo078]

VM version: 2.0.6
Joomla! version: 2.5.6

Dear Sir/Madam,

I'm having really big problems with my mail
When I try to change the status of the order it says:
1 of 1 order reported an error (Translated from dutch)
For the mails layout I use interamind email manager pro

Can someone please help me out!

Many thanks

Sincerely,
Jeroen, Grandcruwijnen.nl