Wondering about the issue with inhomogenous periods

[kschmid]

When trying to access DWPA.de with a 7d period or a 30d period, I get:

1 Failed download:
['DPWA.DE']: Exception("%ticker%: Period '30d' is invalid, must be one of ['1d', '5d', '1mo', '3mo', '6mo', '1y', '2y', '5y', '10y', 'ytd', 'max']")
[100%%*] 1 of 1 completed

respectively
1 Failed download:
['DPWA.DE']: Exception("%ticker%: Period '7d' is invalid, must be one of ['1d', '5d', '1mo', '3mo', '6mo', '1y', '2y', '5y', '10y', 'ytd', 'max']")

as it works for most other symbols, it is probably something on the side of yahoo that specific tickers are only compatible with specific periods. However, I to know something like this beforehand (i.e., before calling)?

[kschmid]

problem was on my side. This error apparently happens when uses old symbols: it works with historical data (and yahoo knows the symbol, but not with shorter timespans, because there is no current data on this..