SSIS Cache Transform – Failed to prepare the cache for new data


Encountered this error today when using a cache transform to populate a lookup cache with some data that I’d look up against multiple times:


I hadn’t set up the cache transform to use a .caw file (more info here), so there were no permissions issues with writing to disk, all that should be happening is writing to memory. Here’s what my SSIS package looked like when the error was received:


In the above we get the number of days worth of data to load and then load each day separately into the destination table (we’re loading each day as we hit some external limits if we don’t). The issue here was you can’t overwrite or append data to the cache. So all that was required was to move the ‘Load the lookup cache’ step outside of the for loop.


After the cache was moved out of the loop, it loaded successfully.