No way to do it.
There are plenty of sites that will tell you to copy this or that DLL to System32 and bypass the check. This works until the next Windows update. the first thing it does is a checksum (or similar) of DLLs and libs. What follows immediately after that is that your system is marked as pirated, with annoying messages and degraded performance.
I've tried this once and it took me several hours on the phone with MS support and a complete Windows reinstallation to recover.
You either buy a local edition of the OS (which will have your language + English - but nothing else) or an Enterprise or Ultimate version. You can blame Microsoft for this crap. Tell them I sent you :)
Don't think it can be done. I know that you can type in Tamil, but to have everything displayed in that language, you'll need the Ultimate Edition of Windows 7. (That is the only reason why I have Win 7 Ultimate.) – wizlog – 2011-08-07T07:18:09.963
Actually, I think it is doable. You may not be able to have multiple languages installed simultaneously, but I think you can get rid of English (or the default) and just use Tamil... If you told use what you wanted to do... What your primary reason for wanting the "Tamil Language Pack" was, we may be able to find you an alternative. – wizlog – 2011-08-07T07:26:56.570
@soandos, its close, but not 100%, not an "exact duplicate". – wizlog – 2011-08-07T07:28:14.480
@wizlog, the answers should be merged at best. – soandos – 2011-08-07T07:36:39.900
Do you have the rep for that? – wizlog – 2011-08-07T07:42:31.920
I am not a mod, I can just mark it. – soandos – 2011-08-07T07:49:27.473
@wizlog i have a user who dont know much english and i want him to use the laptop so english menus, etc will be great.. is this enough information? – SivaKumar – 2011-08-07T09:33:36.450