what documentation about your legal entrance or status in US did you send in the first place?
Here is what I mentioned in another thread.
My Full documents are delivered at Buffalo on June 21st. I sent an inquiry through Buffalo Consulate website on August 20th asking about 2nd AoR. I received standard reply. Today (September 3rd) I received my full package back (without 2nd AoR). Inside notice states that I need to provide proof of legal admittance into USA (I am Indian national). I have 60 days to submit from the date the letter was created, which is August 03, 2010 (this date is stamped with a rubber stamp). This really means I have only 30 days, which is not a problem in my case.
What proof did I provide initially for legal admittance?
I sent my stamped visa in my passport which shows the H1B is issued for 3 years.
What proof Buffalo asked me to furnish now?
1. Entry & exit stamps in my passports (expired or current)
2. Documentation on date of admittance & validity (expired or current)
3. I-797 (H1B)