hikvision DS7616 pasword reset problems

Help needed with admin/password reset on a hikvision DS7616 any help is greatly appreciated. Problem started after trying to reset passwords etc. as I kept being told password is weak please change. Anyway I know what password I put in and it used special characters but after confirming it said a network problem occurred and now I cant access with the old or new codes. Also the hard drive has now flagged up a hard drive error and is constantly bleeping about every 30seconds or so and it seems I need to acknowledge this to silence it but clearly cant without password etc. I written the attempted password down so I really don't understand why this has occurred so please please can someone help me the bleeping is driving me crazy.

Maybe dvr crash and it need tftp upgrade like "format".

please send full serial # i will send u passcode for sadp tool help to reset password.

Many Thanks to all who took the time to read my post and especially to the people offering support it is very much appreciated. However I have been in touch with technical today and the problems have been resolved, the problem appeared to be that special characters in the passwords are not all recognized and the one which I had chosen was a £ symbol. My advice to anybody wanting to choose a special character would be to go to the machine locally and scroll through using the arrows at the top right once in the login menu there you will see them. I was also told that a space is also seen as a character. The hard drive problem was a case that it was full and hadn't overwritten the info etc. I hope this information is of use to others TTFN.