This post is long pending, since I had worked on the topic around 2 months back.
According to GP Installation Instruction, To set up an ODBC data source, enter the name you assigned to the SQL Server when you installed Microsoft SQL Server. A data source name called Dynamics GP also is created using SQL Native Client. If you don’t want to set up an ODBC data source, mark the Do not create a data source option.
It’s very handy (and recommended too) to create the ODBC DSN thru’ GP Installation, when we install GP on a 64 Bit System. We all know that GP is a 32 Bit Application. When we install GP on 64 Bit System, it gets installed with 32 Bit Compatibility.
Typically, on a 64 Bit System there are two ODBC Data Source Maintenance wizards available. One is for 64 Bit and other for 32 Bit. What you open from Control Panel -> Administrative Tools (or Start -> Run -> ODBCAD32.exe), is nothing but default 64 Bit ODBC DSN Maintenance wizard.
If you manually create a System DSN for GP, GP Application does not recognize this DSN at all. We have to actually create a System DSN for GP in 32 Bit ODBC DSN Maintenance wizard, which is accessible from the following path:
C:\Windows\SysWOW64\odbcad32.exe
We have to explicitly open this application from the above path and create System DSN for GP there.
Trust me, both look exactly the same. Application Name ODBCAD32.EXE is also the same for both. But location & compatibility factor is different.
In case, you are stranded when your ODBC DSN is not listed in GP’s Welcome Screen Server Dropdown, on a 64 Bit System, rest assured that you have not created DSN on the correct DSN Maintenance wizard.
VAIDY
Dynamics GP - Learn & Discuss 
Hi there!I have a client who's server just fried, and we are reinstalling all programs including SQL Server 2005 & GP 9.0. I am not being given the option to set up an ODBC source as the manual implies (the portion you quoted above). Consequently, there is no server to choose from when I try to open GP. Do you know why this might be happening? I have uninstalled and reinstalled both SQL Server and GP, and the result is the same each time. Do you think I need to manually create a data source as you've mentioned above?Thanks!
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Hi Kimberly,If you are selecting the option "Do not create Data Source" while installing GP, then you have to manually create the DSN, as mentioned in my blog.And when you manually create the DSN to the server, just make sure that you are creating it in 32BIT ODBC DSN and it's a System DSN.GP does not read any other DSN than SYSTEM DSN.For more details you require, email me to this ID: vaidyDOTdyngpATgmailDOTcom(Replace DOT with . and AT with @).VaidyVaidy
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Hi Vaidy,I'm not even being given that option. No such screen pops up – allowing me to either set up an ODBC or select "Do not create Data Source". I know that sounds crazy!I'm now in the process of reinstalling on a different computer just to see if it pops up there. Otherwise will try to manually create it and see if that works.Thanks for your prompt response!Kimberley
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If this option is not shown while installing, it's imperative that you have to create it manually. In that case, you have open DSN Maintenance from the path that I have mentioned in my post (for 64 Bit systems alone).Vaidy
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Okay. Will do. Thanks!Kimberley
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Do you need to mark the "Do not create a data source" option when installing GP on the server and clients if you have already manually set up a 64 bit config as described above? Thank you
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Hi Kevin,Yup, you do not need to select that option, if it's already created manually.Vaidy
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I created it manually on the server. When I install the client I did not mark the "Do not create a data source" and after that the client is not able to log in with utilities to sync framework because the server block name is blank and it will not allow input. I believe I may need to leave the check box selected on the individual client install. Thanks for your advice.
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Thanks for this post. Just saved me much time / stress.
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Thanks Vaidy, i was not aware of 32 Bit ODBC DSN Maintenance wizard in 64 bit server, and just now know to know why the DSN was not displayed in the welcome screen.Thanks,Maniraja D
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@Maniraja Glad that it helped you overcome that issue. This is nowhere mentioned and that makes this post a bit important for those who suffer with 64 Bit configurations.Vaidy
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Hi Vaidya,Is following scenario will work?GP Application Server – 64 bit GP Client machine – 32 bitThanksSunil Maheshwari
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@Sunil, yes this would certainly work.
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Hi vaidy, thank you very much for this post. You are a big help to more people you dont even know. Unselfish and always willing to help. God bless you. – emerson
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Hi Vaidy ,Is that possible GP Applicastion Server -64 bit works for GP Client Machine -32 bit with ICA ?Any document available for this scenario & also your previous post Vaidy
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And what 32 bit SQL Server & 64 bit windows server combination , any conflict to GP APPLICATION SERVER (especially GP 10)…….3Q in Adv
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