We have just upgraded out core app from EL 3.1 to EL 5. This has mostly gone well. However, when I opened the app.config file in the Enterprise Library configuration utility to add in a new exception handling policy, i got an error:
Error Loading Section connectionStrings
Error message : Object reference not set to an instance of an object.
Although the configuration tool opens and reads the other blocks in, the data access block is not shown. It seems this comes down to the presence of some entries in the connection string section which are intended to stop our app picking up strings from
the machine.config file as follows:
<remove name="LocalSqlServer" />
<remove name="OraAspNewConString" />
<remove name="OraAspNetConString" />
However these are also present in the config file we used with EL 3.1 and the configuration tool for 3.1 had no problem opening the config file and displaying the data access block (although the 'remove' entries themselves aren't shown which is fine).
As far as I understand from http://msdn.microsoft.com/en-us/library/ms254494.aspx the
remove element is a legitimate child of the connectionStrings element, so I don't see why I should be getting any errors at all from the configuration utility. It's most annoying because I have to manually remove
those lines, then open the file in the utility to add the new policy and finally re-add the lines manually again which is a bit of a nuisance. I'm stumped - anyone seen this before or know what this behaviour is about?