As you have discovered the code that you are running on these routers does not support DLSW. To be able to run DLSW you will need to change the code on the routers. It is not necessarily a question of version of code but it is a question of which Feature Set you are using. On the 3661 I have found two Feature sets which will support DLSW. They are:
IP PLUS c3660-is-mz.122-26c.bin
Enterprise Plus c3660-js-mz.122-26c.bin
and on the 2811 I have also found two Feature Sets that will support DLSW:
You need these feature sets to support DLSW. I have listed versions that are approximately the version level that you are currently running to make it easy to see the point. I would suggest that while you are changing feature sets you might also want to consider upgrading to a somewhat more recent version of code, especially on the 3661. Be aware that changing the feature set or changing the version might change the requirements for flash and memory. Also be aware that changing feature sets will usually involve a licensing fee to get the different feature set.
 I see that the response from Harold says that the code on the 2811 is fine. My search of the Feature Navigator does not show support for DLSW in the IP Services feature set. Perhaps Harold knows something that I do not?
We are pleased to announce availability of Beta software for 16.6.3.
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looking for early feedback from customers befor...
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