have you made a spelling mistake, if msgins.dll should be spelt msgina.dll do this
To resolve this issue, use the Windows Recovery Console to extract a new copy of the msgina.dll file from the original Windows XP compact disc (CD). To do this, follow these steps:
1.. Start the Recovery Console. If you do not have the Recovery Console installed, start it from the Windows XP compact disc (CD). To do this, follow these steps:
1.. Insert the Windows XP CD and restart the computer. If prompted, select any options required to boot from the CD.
2.. When the text-based part of Setup begins, follow the prompts; choose the repair or recover option by pressing R.
3.. If you have a dual-boot or multiple-boot system, choose the installation that you need to access from the recovery console.
4.. When prompted, type the Administrator password.
2.. At the command prompt, type cd system32, and then press ENTER.
3.. Type ren msgina.dll msgina.old, and then press ENTER.
4.. Type map, and then press ENTER.
5.. Note the drive letter assigned to the CD-ROM drive that contains the Windows XP CD. It is displayed in a format similar to the following:
D: \Device\CdRom0
6.. Type expand drive\i386\msgina.dl_ (where drive is the drive letter of the CD-ROM drive that contains the Windows XP CD), and then press ENTER. For example:
Expand d:\i386\kernel32.dl_ <ENTER>
Note the underscore character after the "L" in msgina.dl_
The following message appears:
msgina.dll
1 file(s) expanded.
7.. Type exit. The computer restarts.
8.. Remove the Windows XP CD and start the computer normally.
Taken from this KB artical but done on a different file, the procedure is the same for the file msgina.dll
Windows XP Logon Screen Does not Appear and the Computer Continuously Restarts
http://support.microsoft.com/default.aspx?scid=kb;en-us;310396