SymServ (also spelled SymSrv) is a critically important utility provided by Microsoft that manages the identification of the correct symbol tables to be retrieved for use by WinDbg. There is no charge for its use and it functions automatically in the background as long as the debugger is properly configured, and has unfettered access to the symbol store at Microsoft.~~
From the W8 UI, right-click on the version of WinDbg you will use (x64 or x86) then select "Run as administrator" from the bar that pops up from the bottom of the screen. You will then see a singularly unexciting application interface; a block of gray. Before filling it in with data you must tell it where to find the symbol files.
Setting the symbol File Path
There is a massive number of symbol table files for Windows because every build of the operating system, even one-off variants, results in a new file. Using the wrong symbol tables would be like finding your way through San Francisco with a map of Boston. To be sure you are using the correct symbols, at WinDbg's menu bar, select the following:
File | Symbol file path
In the Symbol search path window enter the following address:
Note that the address between the asterisks is where you want the symbols stored for future reference. For example, I store the symbols in a folder called symbols at the root of my c: drive, thus:
Make sure that your firewall allows access to msdl.microsoft.com.
How WinDbg handles symbol files
When opening a memory dump, WinDbg will look at the executable files (.exe, .dll, etc.) and extract version information. It then creates a request to SymServ at Microsoft, which includes this version information and locates the precise symbol tables to draw information from. It won't download all symbols for the specific operating system you are troubleshooting; it will download what it needs.
Space for symbol files
The space needed to store symbols varies. In my W8 test machine, after running numerous crash tests, the folder was about 35MB. On another system, running W7, and on which I opened dump files from several other systems the folder was still under 100MB. Just remember that if you open files from additional machines (with variants of the operating system) your folder can continue to grow in size.
Alternatively, you can opt to download and store the complete symbol file from Microsoft. Before you do, note that - for each symbol package - you should have at least 1GB of disk space free. That's because, in addition to space needed to store the files, you also need space for the required temporary files. Even with the low cost of hard drives these days, the space used is worth noting.
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