Louise,
Thanks for posting.
Usually when someone reports that their pens or wands stop working it means that the board has lost connection with the computer. There are several things that can cause this- we'll usually start by looking at cabling, drivers, and firmware though you mention this happens "after every activity-" Is it specifically at the end of an activity and if so can you go into more detail as to what the activities are, or is it sporadic?
The above may redirect our troubleshooting though initially can you please confirm how you're connected to the board, and if applicable can you test with any and all extensions and adapters bypassed (ie with a direct connection, probably a single length of USB cable)? Can you also kindly advise what operating system you're working on? Can you look to find you Activmanager icon (near the time, generally in the lower- or upper-right corner of the screen), click on it, select Control Panel, and look for your driver and firmware version when the board is connected?
Also, as a last point and hopefully to mitigate the issue as we work through, can you try cycling the connection between the USB cable and the computer or power cycling the board to see if this reestablishes connection?
Incidentally, it's usually inadvisable to include your phone numbers in a forum most like this; I've taken the liberty of editing them out. If you need to contact us over the phone you can find our numbers at www.prometheanworld.com/.../technical-support-numbers.
I've logged this against case 00333305, please let us know your results. Thank you,