Hot answers tagged 2010
CSOM and REST was introduced in SP 2010 so you wont be able to use that with 2007. SOM is an option but requires that your code runs on the servers of each farm. SharePoint Web Services will be your best option if you need to support all three versions with the same code from client computers. Lists Web Service (/_vti_bin/Lists.asmx) for getting libraries ...
CSOM: will work in SP online, SP 2010, 2013 and most probably 2016 REST: will work in SP online, SP 2010, 2013 and most probably 2016 OOTB Web service: will work in SP 2007, 2010, 2013 but maybe not in 2016 (and maybe not with future versions of SP online) Creating your own Web service with SOM: will work in SP 2007, 2010, 2013 and 2016
Use this URL to get the item: http://siteUrl/libraryName/Forms/AllItems.aspx?FilterField1=ProjID&FilterValue1=projIdValue
If the user for some reason is accessing it with a IE 64 bit you will not able to see Datasheet view (to check this is the case see if the user sees the button open with explorer as grayed out). Datasheet view works with Firefox and Chrome however I noticed that unlike IE, those 2 browsers do not allow PASTE into the datasheet view.
That may be because your DLL hosting the code is deployed into the \bin folder and not into the GAC. GACed DLL have Full control, while \bin DLL have a limited set of permissions (that can be changed in a .config files). You can ensure your main DLL is deployed to GAC in Visual Studio: select the project in Visual Studio, and change the "Assembly ...
The client object model was created in 2010. CSOM did not exist in 2007. So I would recommend the server object model.
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