I agree with Bob Kovacs, that your problems are probably more a sign of the current economic times, and not targeted specifically to you or your business. Once we get back into a softer financial market again, you will probably find it way easier to get the business credit you are looking for.
Have you ever requested a copy of your business' credit report? Perhaps there is something on there, a mistake that needs to be fixed, and you just don't know it. This is also good practice for one's personal credit. For all you know, you have been a victim of identity theft and there are unknown loans on the credit report that are now barring you from getting proper credit on your own.
Another suggestion I have, being in insurance, is to finance your annual insurance premiums through an insurance financing company like AFCO in the USA or CAFO in Canada. While some insurance companies offer a flat 3% monthly payment fee, the insurance financing companies interest rate applies only on the decreasing balance, so even if their posted rate is 5%, often it ends up being cheaper to finance through them. Plus they finance almost every business because they will use your insurance policy(ies) as collateral; if you don't pay your monthly payment, they cancel your insurance and collect the refund. One more thing, the insurance financing companies don't register their loan, so it frees up your regular credit for other purposes. It's easy to set up; your insurance broker gets the quote and contract for you - so it's not like you have to go to the bank and apply for a regular loan. Then afterwards, you can use the loan contract you had with the insurance financing company as history towards building up future credit because they also provide reference letters confirming that payments were made on time and on full.
I'd actually be curious to know how many of you here at CT finance your insurance premiums this way? It really is a smart way of managing your money, and as most of you know the annual insurance bill is not a cheap one. Most of my accounts are financed this way, even if the business had the cash available to pay the full premium at renewal time. I'm not an accountant, but if you know how to read a cash flow statement, they give you one with the quote when you are considering whether or not to take the financing contract, and apparently, their interest rates are such that most of the time you actually make money by keeping the full payment in your own bank account and only paying month to month.