There may be a couple of reasons for it. Depending on the reason, there are several potential solutions. Here are all of them:
1. Make sure you have at least these values in the MetaTrader settings. Having less might result in such errors (see screenshot)
2. Make sure that all pairs you wish to trade are in the Market Watch.
3. If both are correct, click through all the timeframes of every pair this error happens on.
4. If that doesn't help, reinstall the terminal.