Software Deployment

As much detail as possible is helpful.

You running the MSI from a network drive? Local drive? Any relavant files in the same folder as the msi?

How are you running the MSI, from a command line such as: --> msiexec /i application.msi

any transforms applied? any other command line switches?

RE: >> but nothing happens as a user but nothing happens as a user

Any Group Policies or other restrictions on the "user" ( I'm assuming you mean "User" in the Microsoft sense, as opposed to Power User).

Sounds like problem with lack of permissions for regular users.
Use Process Monitor (ProcMon) from Sysinternals/Microsoft.
Login as the regular user, start ProcMon as an admin-user (use runas) and then look for Status: ACCESS DENIED. You then need to decide if you want or are able too depending on company policy elevating/change the permission on these failing resources. Sometimes if the application tries to write a ex. HKLM registry key but is denied try to create that registry key and see what more you have to create for the application to function correctly.

The *first* thing to do is run the install with a verbose log:

MSIExec /i [path_to_and_name_of_MSI] /L*V [path_to_and_name_of_log_file] [other command-line arguments]

Once you know where the error is occuring, you may not need to bother with a process monitor like ProcMon, although that will show exactly what needs permissioning (if that's the issue). Equally, if the log shows file access is the problem, you can turn off the registry display in ProcMon and vice-versa.