Can I resolve QuickBooks won’t open problem? Help me!

While opening a company file, I am watching carefully that QuickBooks is very slow to respond, or fully not responding properly. I am extremely disturbing by seeing this issue, so I look for quick remedies for this QuickBooks won’t open. This issue can take place due to many causes. I don’t have complete knowledge about this issue; therefore I want to take quality assistance from a certified QuickBooks support techie. So please anyone recommend me the right ways for resolving this issue as soon as possible.