Serial Key should work fine in Lightroom 5.7.1 version because its a update to 5.7 version not a up-gradation.
Please let us know the exact error message you are getting.
The message just says Serial Number
The serial number you entered is invalid. Please try again. If the problem persists, contact Customer Support.
Do you need the serial number I entered?
Information Security Consultant
Mobile:...... . ... ....+44 (0) 7 552 555 555
OneNet Express:.+44 (0) 118 9670 700
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Did he create just me in his image, or every living thing?
If 5.7.1 was installed on the same computer, there shouldn't have been any question about a serial number. If 5.7 was running properly it should have just been an update. Did you install 5.7.1 on a different computer?
It’s the same computer – in fact, both versions were originally showing.
The serial I used starts 1160-4005-… does this look right?
Yes, the serial number looks to be correct. But I don't understand why it was necessary to enter the serial number. Lightroom 5.7 & 5.7.1 are the same "version" running under the same serial number. 5.7.1 is simply an update, and it should have simply installed and your work should have continued. Where did you download the update from?
No, that's not it.
If you had Lightroom 5.7 installed, then you do not need to enter a serial number into Lightroom 5.7.1.
Did you at any time download and install a trial of Lightroom CC?
I don't know if this link is any better. But you might try downloading 5.7.1 from here and give it a try. A simple update like you supposedly installed should not have caused any problem with the serial number.
Not Knowingly – there was no warning that it was eval only. The version I downloaded offered me a 30 day trial or the option of registering my version.
If you have correctly downloaded and install the Lightroom 5.7.1 version using the above offered link & then simply register/Activate the software using the Serial number.
However, if its still says trial, refer the below link and try Solution #4 to fix it.
Let us know if that helps.
Thanks so muich for your help with this. It would seem that, as you suspected, I had unwittingly downloaded the wrong version of the update.
The version you pointed me to works perfectly, and it also removes the 5.7 version that was still present with the previous update attempt.
The speed and effectiveness of your responses really has inspired confidence in this forum.
Very best for 2016.