Open File Options for each file and make sure that you have "log in using" selected with admin entered into the account box and that the password box is open. Make sure that you have the admin account defined in manage | Security with no password defined for it. These are the standard default settings for new FileMaker files and will not request a password when you open the file.
For an existing file that is asking you for a password, try entering admin in the account name box and leave the password box empty to get past thise dialog and get the file open with a full access account so that you can use File Options and Manage Security to return the file to it's original unprotected state. This only works if the admin account still exists and has no password defined for it.
I am having the same issue. I have tried to use admin and no password but to no avail. Is there any way to get into the file?
Is this a file that you created recently or a file created by someone else?
Is it on a Mac system or Windows?
I created the file last August, I haven't accessed it since January and when I tried to pull it up the other day it asked for a password, and I never set one initially. It is on a Mac. I have tried the admin/no password combination, and this did not work. I can pull up other files created at the same time and the same way.
Is there any chance that you or someone else set it up with a password and now you don't remember? This isn't something that should happen spontaneously. Admin and no password works when the user didn't actually set up an account in manage security because it is the default settings that are created in every new account. If it does not work, then a specific account must have been set up in manage security.
Issues also to consider:
If your file opens another FileMaker file, the password dialog could be popping up when it attempts to open the other file.
On Mac systems, a tool called "keychain" (I don't own a mac) can be set up to automatically open the file with a password. If that tool's settings are changed or the file is moved to a different computer, suddenly a user is asked for a password when opening a file that did not previously ask for when when opened.
Same problem. Existing file suddenly requires an account name and password, after being opened and closed for years. Running Mac Maverick 10.9.1, and FMP 12.0.5. I suspect something crossed in the new security updates with OSX 10.9. The only alteration to the file had been adding a new layout a week earlier, with no apparent problems. Whatever. Anyway, the suggestion by PhilModjunk to enter "admin" as the account name, and leave the password field blank, opened the file. I then opened settings, Security management, etc: absolutely no evidence of any previous change in settings. So..., I put in new settings anyway, as a precaution. Has opened/closed just fine since. Thank you very much, Phil. Don't know why this worked, but very very grateful.