I just wonder why it is so hard to contact them by mail....and to get a response..
This is a sensitive topic to me for reasons I won't get into at the moment. Remember for communications to occur both parties have to ensure communications take place. You may be sending email, but you don't know if they are receiving your email.
There could be multiple reasons......
1. The company isn't very IT literate and isn't proficient with email. I've had good experience with both Carlos and Sandy in the past, but my experience is dated. For example, the paint shop I'm using checks their email only 2-3 times per month. I doubt this is the case for GRT.
2. You ISP has been blacklisted. It does happen occasionally for all the wrong reasons. All it takes is for another user that uses your ISP to start spamming the world intentionally or not intentionally due to a virus or trojan horse. This would then cause their ISP to filter your email if they subscribe to the blacklist.
3. Are you using an appropriate email address? I always prefer to send to an individual as oppose to a distribtution list (i.e. send to Carlos directly, instead of "sales" or "info". For example, Carlos is registered on VAF. (
CarlosF@grtavionics ) Click through the links and send him an email directly through VAF.
4. I know that you're international, which makes calling potentially more expensive and you have to cope with the time differences. I've found with vendors that cater to the experimental market it is much better just to pick up the phone and call. You will get better information in real time. If you're international, just use a service like skype to minimize the expense. I know of one vendor that even uses a web cam and skype to troubleshoot issue in the plane. They can see what you see.
5. If you turn on delivery receipts, you can validate the email was delivered to their email server. Turn on read receipts and you have about a 50/50 chance of knowing is somebody actually read the email. Some folks turn off this feature in their email client.
6. Sometimes small businesses have IT problems that they don't or can't get fixed quickly. I know of one business that didn't know they weren't getting email until somebody called them and informed them.