Too Many Sensors Nearby
If Too many sensors nearby is displayed at the start of your exercise, your Polar RS800 training computer is within the transmission range of two or more Polar s3 stride sensor W.I.N.D. / Polar s3+ stride sensor / Polar G3 GPS sensor which are saved in the training computer's memory and both/all of them are moving.
If you have more than one stride sensor / G3 GPS sensor in the training computer's memory (i.e. you have 'taught' it more than one sensor), make sure that only the one stride sensor / G3 GPS sensor you wish to use is in motion when starting the exercise. Your RS800 should be locked to your stride sensor / G3 GPS sensor before you can move any other taught sensor. This way your training computer will only acknowledge the signal from the stride sensor / GPS sensor you want.
If you wish to have only one sensor in the training computer's memory, go to Settings → Features → S sensor and select Remove all. Now teach your stride sensor / G3 GPS sensor again.