Hi Mark See,
Thank you for your question. We have a page on the problem:
Having troubles opening the CHM file?
Basically, try the following two things:
1) Copy the *.chm files to your local hard drive if you access them over the network.
2) Right click the chm, click properties, and then click the
Unblock button.
Do not hesitate to contact me back if this does not help.
Best wishes,
Nick
the Telerik team
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