I've spent all afternoon and all evening trying to upgrade from 129 to the latest version but to no avail. Everytime it's a different problem, everytime is some error here or there. 500, 400, php change line 3 million, I look on these forums and I dont know where to start - I give up. Zenphoto is absolutely fantastic and it does photos better than anything else out there. But all this code and problems baffles me, so I'm hanging up my hat.
And your upgrade instructions, delete all files in base directory eg xx.php... What's that supposed to mean? All non folders? Only .php files? Anyway, good job on everything when it works and when you come up with a one click upgrade please tell me. Because I've had enough.

I am pretty sure that anyone wishing to help you would need some better details than what you have posted above. Seems more like a frustrated bitch than a call for help.

And your upgrade instructions, delete all files in base directory eg xx.php... What's that supposed to mean? All non folders? Only .php files?

I am not sure from whence you got this text. The actual instructions read

3.Remove the “zen” or “zp-core” folder, the theme folders that were distributed with Zenphoto, and the files in the home dir (index.php, rss.php etc.) that came with the distribution. (If you are upgrading from a Zenphoto version prior to the instantiation of the zp-core folder, take note of the database credentials in your zp-config file, you will need it in step 4.)

Those seem pretty explicit to me.

I've tried those instructions and I keep getting 500 errors.

"and remove..... the files in the home dir (index.php, rss.php etc.)" is not explicit. I'll give you an example of some of the files in my home dir.

zenphoto.package
htaccess
all the php files.

Do I really wipe these all out? Anyway, I tried to setup a test database so I wouldn't keep ruining my live version:

http://appl.prettysnappy.net/

The last attempt here was what I got when I tired to install a new version, and then import albums, cache, backup etc...Sometimes, strangely, doing things on a separate database actually ruined my live version too.

[i]"and remove..... the files in the home dir (index.php, rss.php etc.)" is not explicit.[/i]
We are always in for improving but this is really explicit. Of course you should not remove your /albums folder. After you downloaded one of the two archives from our site, extracted it and uploaded those to your server either into the root of that server or within a subfolder (for example "zenphoto"). That is the home directory of Zenphoto... It is that simple.

[i]Sometimes, strangely, doing things on a separate database actually ruined my live version too.[/i]
If you used a separate database that can't really happen. Unless you did use the same database with the same table prefix. In that case the new install would overwrite the database data of the other one of course.

I would really recommend to start fresh install following our instructions.

I would love to do a fresh install, because that works like a dream. But I have a number of albums with ratings and comments in the 1.2.9 version which I would like to retain.

And the second I try to migrate the 1.2.9 version to the 3.0.1 version it tells me I have a duplicate administrator. If I paid you would you do it for me?

Would you be able to advise what I can do about this: ?

http://appl.prettysnappy.net/zp-core/setup.php

Should I press "Go" ?

******

It was too tempting, I pressed Go. Didn't work. Cant process request or something like that.

Well, we are getting somewhere now that there is at least one specific error you have given us. You need to download and use the nightly build to get past the "duplicate administrator" issue. BTW, this has shown here before, so also a search on the errors you have encountered might save you the turn-around time for one of us to see your post and respond.

As to the final post, since you have apparently removed the setup files (as recommended) we cannot see what you saw.

I'm not a ZenPhoto admin or developer, but a user who's being doing a lot of upgrading recently. There are two approaches:

1. delete EVERYTHING except the "albums" and "cache" folders from your /zenphoto/ install location (also leave the "backup" folder if you have made database backups, but if you haven't made any this won't exist yet). Take the downloaded latest version, and upload everything except those two folders (you need to keep the originals so that your photos still physically exist somewhere). Make sure the three folders - themes, plugins and zp-data - are writeable as noted in the instructions (CHMOD 777 on all three), and make sure that /zp-core/config.php.example is copied as /zp-core/config.php - then edit the file to include your database username, password and database name.

2. what I find works is to do as above, except instead of deleting the old install, simply create a new folder (eg zp_1.2.9_old) and simply move the old files into it. This should leave you with "albums", "cache" and "zp_1.2.9_old" folders, and continue with the upgrade as before. This is what I do and I can now move between older and newer versions at whim simply by moving the existing version into its folder, and moving the other version out into the main /zenphoto/ folder. This assists in version-based troubleshooting.

Also, since you are using 1.2.9 at the moment, make sure you use the backup function to make a backup of the database before trying any upgrade! This way, if you accidentally overwrite your database entries, you can restore them again (it is a good idea to do this for the entire database and indeed website on a regular basis). Remember that a database user (eg. "zenphoto") which uses tables prefixed with "zp_" will still have its entries overwritten by a different user (eg. "zenphoto_2") if this other user is using the same table names and prefixes. Different users in the same database can still cause issues, and perhaps this is the mistake you made with your test install.

@sbillard - Many thanks indeed.
@filecore - Huge thanks for such a detailed response, I've printed this out and I'm going to try it step by step. Thank you for everyone's efforts on this, greatly appreciated.

@filecore - worked like a dream! Thank you!

I also am getting the dreaded blank screen after upgrade to 1.3.1, skipping some versions from my old version to 1.3.1.1. I followed the instructions as best as I know how. I did everything that 'filecore' suggested. Heck, I even uninstalled the whole nine yards and did a clean install. Blank page. I uninstalled again and allowed my web host (Powweb) to do an automated install - blank page. Went back to 1.2.9 - Viola! Works like a champ. After the 1.2.9 worked, upgraded to 1.3 ... upgraded nicely. Tried to upgrade to 1.3.1 - blank page. I will get all info I can and add to this post later today. This is a work in progress, eh?

There are no known upgrade issues with 1.3.1.1. But your post is not clear--are you upgrading to 1.3.1 or to 1.3.1.1. If the former, skip that and go straignt to 1.3.1.1.