Tortoise CVS problem for a CVS expert

Avg Bid (USD)
Project Budget (USD)
$30 - $30

Project Description:
i have since one month a massive problem to access CVS (checkout) , update or upload.
My server is a virtual server. I can access by FTP but not anymore with CVS.
We are several persons developing.
As soon i start checkout after some seconds i get error "cvs [checkout aborted]: reading from server: error -1"to c
A programer in china can access with my account details, he has no problems. Only me, i cannot access.
So i need an idea what to change or to do.
I installed meanwhile 3 times a new cvs version. No result.
I switched off firewall and bitdefender. No result.
We changed the port (normaly 2401) to another one. No result.
We created a new account for me. No result
The idea which helps will be awarded and payed. Honestly and straight.

Additional Project Description:
02/20/2013 at 23:16 EST
On our VS we run CVSNT as CVS Server.
I am based in Malaysia right now. Until christmas 2012 all worked properly.
Then nothing anymore. Made no change. Only change what happened that license of bitdefender had ended.

Skills required:
Software Testing, Technical Support, Troubleshooting
About the employer:
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