Question

Why am I getting a Invalid parameter poi(adr+4) when I run the following command in WinDbg while debugging a dump file?

.foreach ( adr { !dumpheap -mt 66df13d4 -short } ) { !do poi(adr+4); }

The following shows that the value of adr is getting populated just fine.

.foreach ( adr { !dumpheap -mt 66df13d4 -short } ) { .echo adr; }

I want to get the contents of a .NET string variable that is stored at the 4th offset of a System.Web.Caching.CacheEntry object.

Answer 1

You need to have spaces around adr or use ${adr}. This is documented in MSDN

Note When the string Variable appears within OutCommands, it must be
surrounded by spaces. If it is adjacent to any other text — even a
parenthesis — it will not be replaced by the current token value,
unless you use the ${ } (Alias Interpreter) token.