Issues With Modem Provided By Hcl With Hcl Mtnl Pc



My parents in Mumbai recently purchased a MTNL HCL PC model no. 2 ( comes with a HCL branded ADSL2+ modem, as shown on HCL website) and applied for MTNL Triband.
The MTNL Engineer came after 10 days and tried configuring the modem, but could not get the internet working.
Unfortunately I am out of India for long-term, and my parents are not computer savvy.
What I understood from my father was that after configuration, the MTNL engineer was getting "Page not found" in IE. He asked if HCL provided some kind of manual with the modem, but there's none. The HCL dealer / customer service were of no use.

My suspicions:
1. Could be DNS issues.

My questions for you all:
1. Anyone having bought the HCL MTNL PC and got the MTNL Triband successfully working?
Are there any subtleties/known issues that we should be aware of?
2. What is the make (OEM) and model of the modem provided by HCL? I am pretty sure they don't manufacture it; they just rebrand it. If I get to know what modem it is, at least I could get specific model-related help.

Any help is highly appreciated.