I ran into this situation in the Paris hotel. I was given three sets of id/pwd for three devices. While my iPhone and Macbook worked fine, the iPad stopped showing the login screen after some time. I tried all the suggestions in this an other forums - nothing helped. Then I decided to use the id/pwd combo that I was using with iPad on a different device. After that my iPad "recognized" that the old id/pwd was invalid and showed me the hotel's login screen.
Now that it works, I'll also install a couple of other Web browsers on my iPad. If it'll happen again, I'll try to go online from another browser.
After my iPad was INOP in my Comfort Suites hotel for 3 days I finally figured out my Internet connection problem.
My iPad worked for only the 1st 24 hours after initially setting up a wifi connection. After my time was up, something was blocking the ability to re-register with the hotel website to get me back on the Internet. I tried all of the tips and tricks listed in other posts and reset literally everything imaginable and still could never get an Internet connection even though wifi settings were showing a valid connection.
Here's where I think the problem lies: Hotels use a series of wifi range expanders and if your iPad gets hung on a range expander that wont let you re-register your wifi, then the fix is simply done by turning off your wifi and going to the hotel lobby or other hotspot within the hotel and then re-enable your wifi.
As soon as I did this, my Internet was restored and I was able to re-register with the hotel website and then went back to my room and everything worked again.
I have been to so many hotels in the last few months and always had the same issue - it would connect but hang on a blank screen or come up with some error about not being able to get a secure connection.
Having read a few suggestions on this forum I fixed this issue and this is as follows:
Please note I had also done the following:
You may find you have to renew the connection once in a while but hope this helps.