I had a similar problem when I started my company many years ago and using a hotmail account (taught me a lesson!)
I am surprised that places are still doing this. Gmail should be using SPF and all the other techniques that will come up as "not spam" to the mail servers of the companies you are dealing with.
It is possible that they are either ignoring you (sorry!) or just have a policy to block email from free accounts.
If you don't mind me saying - and please ignore if you think I am interfering. If you are starting a business, register a .com or other domain. They can cost peanuts and if you find the right host, you can get mail included. It will make you look much more professional than using a free account and you should not have these problems. In my business, it felt like the turning point from amateur to (well slightly more) professional.
Does Gmail really filter spam based on other people's flags? Can you provide a reference for this? – endolith – 2010-07-25T22:47:18.047
Well I can't imagine it is a string of letters since it is just my name (james). Is there a way to check if my e-mail has been flagged? – James Simpson – 2009-09-04T15:54:55.720
I personally do not have a email address to where you can check with Gmail if your accound has been flagged as a spammers account however these links might help you out..
If you are sending emails in bulk check this link.https://mail.google.com/support/bin/answer.py?answer=81126
Help forum for Gmail users. http://www.google.com/support/forum/p/gmail?hl=en