The time it took between pressing F5 and our web application loading in IE rose from around 16 seconds to around 55 seconds, after we increased language support from 2 to 8 languages by adding .resx files to App_LocalResources.
Watching the Output window during this time, all the lines about loading symbols appear quickly upto the 'App_LocalResources' one, and then they just trickle along.
After two days of investigation, it appears to be closely related to SVN. The problem doesn't appear until the new resx files are committed. If we move the hidden '.svn' folder out of the 'App_LocalResources' folder, the time drops down to 18 seconds. So I suspect the files under .svn are confusing Visual Studio for some crazy reason.
We've tried all the solutions others suggest to do with slow loading symbols generally, e.g. deleting breakpoints, changing symbol server and symbol caching settings, calling aspnet_compiler in a post-build event, and they all had no effect. The latest thing we tried is to to tell VS only to load the debug symbol for the single main DLL, using Tools > Options > Debugging > Symbols > Specify Modules, but it appeared to ignore this and attempt to load symbols for everything.
If it's really just because of .svn folders are confusing debugger than you could upgrade your SVN client to 1.7+, which uses just single .svn folder at root of your working.
