Working with SQL Server CE under vista (UAC)
in [CSharp]
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From: allmhuran on 26 Feb 2010 17:52 I have a .net 3.5 project written with visual studio 2008. I also have a setup project for this application. The project includes a SQL Server CE database, and needs to read from and write to this database. The database file (sdf) is included in the application project as type "content". The setup project sends "content files" to the users application folder. This works under XP, but not under vista. When the program is run, an error occurs, saying that permission is denied on the database file. What is the solution to this for vista? Do I need to change the way the setup project is configured, or do I need to write extra code in the application? Do I need to do yet another different configuration for windows 7? I only have an XP machine on which to develop and test, so this is very frustrating. T.I.A.
From: Alberto Poblacion on 27 Feb 2010 04:13 "allmhuran" <allmhuran(a)gmail.com> wrote in message news:96ca21ef-41a9-4d1a-a24c-0e0910cac574(a)c37g2000prb.googlegroups.com... > [...] > The project includes a SQL Server CE database, and needs to read from > and write to this database. > The database file (sdf) is included in the application project as type > "content". > The setup project sends "content files" to the users application > folder. > > This works under XP, but not under vista. When the program is run, an > error occurs, saying that permission is denied on the database file. This is not a good idea. Ordinary users should not have write access to the folder where the program executable is located. Even if it does work under XP (probably because you are an administrator of that computer) it is still not a good security practice even under that operating system. And in Windows Vista, as you have already found, it will not work even if you are an Administrator, because UAC "downgrades" you to the permissions of an ordinary user. If you really are going to always run the program as an administrator, you can add a "requireAdministrator" parameter to your application manifest so that it elevates privileges when it is started. But if your program is intended to be used by non-administrative users, this is not the way to go. > What is the solution to this for vista? Do I need to change the way > the setup project is configured, or do I need to write extra code in > the application? Do I need to do yet another different configuration > for windows 7? Ideally, you would install the database file in a folder that is adequate for the user data, such as in a subfolder under SpecialFolders.MyDocuments. Not only for Vista, but also for XP. This means that your setup program would deploy the "model" .sdf to the program folder (as you are currently doing). Every time your program is started for the first time by a new user, the program copies the model sdf from the program folder to the Documents folder of that user. Then the program uses that copy for read/write access. Don't worry about Windows 7; if you make it work for Vista, the same configuration will also work for Windows 7. > I only have an XP machine on which to develop and test, so this is > very frustrating. A suggestion: test it under XP with a non-administrative user. This non-administrative user should NOT have write access to the Program Files folder, so it will behave the same as on Vista.
From: allmhuran on 27 Feb 2010 13:34 Thanks for the reply! > This is not a good idea. Ordinary users should not have write access to > the folder where the program executable is located. Fair enough. I have no expertise with this kind of thing, I'm a database designer/admin, not so much an application developer anymore, so I just took the defaults in the visual studio setup project. About 90% of the programs I have on my own computer work this way too, reading from and writing to configuration files underneath the program directory. In fact, as a user I always hate it when a program goes and hides config data under the ridiculously long application data path :D > This means that your setup program would deploy the "model" .sdf to the > program folder (as you are currently doing). Every time your program is > started for the first time by a new user, the program copies the model sdf > from the program folder to the Documents folder of that user. Then the > program uses that copy for read/write access. The database structure itself is written to support multiple users within the one sdf. Is there a correct "special folder" to install to such that all users of the machine have access to the same database file? That is to say, I do not want to create a copy of the sdf for each user, because the sdf contains shared data.
From: allmhuran on 27 Feb 2010 18:16 I've looked through the available options in a visual studio setup project for the defaultLocation property of a directory on the target machine. I can specify a "User's Application Data Folder", but this is on a per user basis. I don't seem to be able to find an "all users" folder option. The visual studio documentation also makes no reference to such an option. But I know such an option exists in XP, for instance, the "C:\Documents and Settings\All Users\Application Data" path, and I can only assume a similar path exists in Vista and in Windows 7. So I guess my real question is this: How do I tell an installer project in visual studio to output the .sdf to the special system folder for all users application data?
From: Family Tree Mike on 27 Feb 2010 20:31
On 2/27/2010 6:16 PM, allmhuran wrote: > I've looked through the available options in a visual studio setup > project for the defaultLocation property of a directory on the target > machine. I can specify a "User's Application Data Folder", but this is > on a per user basis. I don't seem to be able to find an "all users" > folder option. The visual studio documentation also makes no reference > to such an option. But I know such an option exists in XP, for > instance, the "C:\Documents and Settings\All Users\Application Data" > path, and I can only assume a similar path exists in Vista and in > Windows 7. > > So I guess my real question is this: How do I tell an installer > project in visual studio to output the .sdf to the special system > folder for all users application data? You need to add a custom folder to the "File View" in the setup project. Set the DefaultLocation property of the custom folder to [COMMONAPPDATAFOLDER]. You should add a folder name specific to your app under that folder however. -- Mike |