data quality problem

I'm using software with trimble 4000sse GPS receiver since last month.
I'm not found any problem with it.
but last day I get the data around 4hrs and handover to our Engineer,
after processing data he said data quality is not good.
He didn't explain any thing to me. I done one job before with this
software and same machine(trimble 4000sse and compectL1,L12 antenna
type)
I've no idea from where I'm worng
So could any one help, inform me wht will be happen with data.
Please help in this way.
Thanks and best Regards,
Asim Qadeer
qadeer.asim@xxxxxxxxx

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