So, okay, at first I wanted to mention that I did try updating Cookie.txt, with new gog-al value (but forgot during the message editing). Updating cookie file didn't change the situation at the time.

Just now I checked out gogcli instructions on GitHub again, and noticed that
sessions_gog_com=<value taken from gog.com>
gog-al=<value taken from gog.com>

are both needed (missed that while checking the same issue with gogcli alone, I just reused GUI cookie file with only gog-al, my bad, might have realized what to do with GUI).

I added "sessions_gog_com=" with respective value from browser to Cookie.txt in GUI folder, with new gog-al value and now everything works.

I didn't change Cookie.txt file ever since that "Download All" odyssey, back in April.

Do you have/need "sessions_gog_com=" value in your Cookie.txt?

No, I realized early on, that it didn't appear to be needed ... at least for me.

Good news that you have everything working again.

I just want to say thank you for that suggestion, it was the issue that was causing me grief, and thanks to finding your post, is now solved!

I was having the same issue as guardianali after copying over my GOGCli folder to a new PC, and was losing my mind. Everything worked great except my downloads would always fail. Made a new cookie.txt and my downloads would fail. Redownloaded GOGCli and the GUI and got it all set up; the download would fail. Finally came to the forums looking to see if there was any other users having this problem or any solution I could find, and lo and behold: the folder I was trying to download to was set to Read-Only for GOG knows whatever reason. The one thing I never checked or even thought about. After unticking the “Read-Only” box, downloads are working perfectly again. Ugh!

Good to know you got it solved.

I really must get around to dealing with my issues with GitHub, and upload some updates, because updates have continued on a regular basis, and my GUI can do so much more now, including a bunch of fixes. I am up to v6.8 now.

A heads up, for those that might be interested in such - an MD5 database.

I'm currently working on a complimentary program, that some folk might like, especially those that don't use Galaxy or a 3rd party downloader, and just use the browser links to download GOG game files.

At this point I am calling it MD5gog Bank.

Basically it is a database program for MD5 and Bytes values for GOG game files.
It's also a program based on folk here sharing and contributing, and will really only work well enough if a good number of folk here do that.

The program features drag & drop onto a drop zone.
What you can drag & drop is a game file, or a Manifest.txt file from my GOGcli GUI program, or the gog-manifest.dat file used by gogrepo.py users.

The manifest files will be scanned and data from them entered into the database. The data is MD5 values, Bytes values as well as Game ID and Title, along with related file names of course. Existing entries are skipped. It may also include a drive serial and PC user name, for assistance with verifying created entries, but I am still pondering over that.

You can also validate the MD5 or Bytes value of a game file, if it is present in the database, or create those values, which can then be later verified by other users (hence the probable need to differentiate between users).

The program also supports the use of 7-Zip to test game extras zip files.

I'm going to all this effort, because yet again GOG have changed something in their API/SDK, and bad metadata is being returned for some game files ... again. Having a slow single thread connection to GOG, can mean a long time taken to get MD5 values for some game files.

At the moment the program is just using a simple basic INI file database, but if enough interest is shown, I will look into reviving my SQL know how and use an SQL database instead, which should give a good increase with importing speed when the database grows large.

The idea, is you share your database file (and program) with others, who add to it and or test with it, and then share the database file back etc.

Validating is currently working, and most of the importing code is done, and once that is complete I will work on the create and add side of things.

I will likely end up giving the program its own thread, but if you are interested in this project, and want to give me written encouragement, you can do so here for now. Due to the nature of this program, I may not bother to set up things to share etc if the interest is clearly not there. Viability relies on a joint community effort.

See the screenshot.

DISCLAIMER
This program is not being developed by or contributed to or supported by GOG.com, or even endorsed by them.

Alright, I have completed the IMPORT code, with the exception of a manifest file created by gogclic.exe, but not built by my GUI, as I would need to see one that has more than one game in it, just to see if there are any differences that might impact.

If anyone wants to play with my program as it is, no CREATE or ADD yet, then you can grab it from MEGA.

Download from MEGA

Please give me some feedback if you do try it.
And of course, share your 'Database.ini' file here if you have imported entries to it.

The zip file (946 Kb) also includes my 'Database.ini' file (1.63 Mb), which currently contains values for 11,648 GOG game files.

IMPORTANT - If your AV program complains about my program, then please use VirusTotal to allay any fears. The compiled files of the programming language I use (AutoIt) often get false detections. You would then need to add an exception to your AV program for my program.

NOTE - Alas, only Windows is supported, though you could try Wine etc. Usually the programming language I use, doesn't work well with Wine or it might be a matter of how I do my coding. If you have success with Wine etc, I'd certainly like to hear about it.

ADVISE - A side benefit no doubt, for all Offline Installer downloaders, is that the database could include MD5 and Bytes values for a wide range of file versions for a game, perhaps all ... dependent on the contributors of course.

--------------------------------------------------------------------------------

My current thinking in regard to ADD and CREATE, is to require InnoExtract testing for installer files (EXE and BIN) and 7-Zip for game extras files, plus the Linux and Mac installers. A side benefit of using InnoExtract, before going onto creating an MD5 value on success, is that the top of the output file contains the Game Title and ID.

The usual process for InnoExtract testing, is to use the EXE file to test that and all related BIN files. Testing with InnoExtract can be a very lengthy process with large installer files ... essentially it is checking every file within the EXE or BIN archive, against the included manifest list that has MD5 values for every file, so with a lot of files, especially big ones, it can take a long time.

How powerful your PC is, will certainly be a factor when it comes to speed of InnoExtract testing and MD5 testing and creation, plus importing to the database.

It is with some reservations, that I finally share the latest update of my GUI program for gogcli.exe.

GOGcli GUI v9-2 is no longer the simpler beast it used to be.

I have held back from sharing more recent updates, because I don't really have the time to create more tutorials or give much instruction.

The 3rd party free program, curl.exe is required for some data retrieval and can optionally be used for downloading. You can even use it with aria2 or Free Download Manager 5 to gain a significant download speed benefit. Be advised though, that FDM5 is tricky to setup.

I am no longer providing via GitHub. You get a Rebrandly link (for download counter) for a MEGA download link.

I don't recommend using my GUI, which also requires latest gogcli.exe (24.1), unless you are fairly savvy with software.

DOWNLOAD

GOGcli GUI v9-2 has had a lot of bugfixes, improvements and new features since I last uploaded.

For those of you willing to try it, Enjoy!

Discovered a bug in GOGcli GUI today, that crashed the program due to a missing ampersand in error dialog code, when your cookie text file no longer works ... mine needed updating, hence the discovery.

I've updated and uploaded the fixed version, but not given it a new version number, so hopefully the download link will still work, as I just overwrote the last version at MEGA. Please let me know if that is not the case.

In any case, renewing your cookie text files, would prevent the dialog error crash, if it had occurred for you.

I discovered another bug, but very minor, and with a feature perhaps never used by most folk.

It is related to an issue that I posted about here.

So I fixed that bug and added some supportive feedback for that issue.

In regards to that issue, most if not all users of my GUI, may never experience it ... but just in case.

I changed very little, so once again, not worth a version number update change, so the same download link two posts back still applies.

GOGcli GUI v9.3 update is now available from MEGA via Rebrandly.

I thought to add a better & quicker method of stepping through game titles, that are marked in red (or orange) as updated.

Not sure why I didn't think of this approach before, because it really is the best way to jump to them all fairly quickly, one after the other, starting with the most recent update first.

While I was doing the GUI update, I also decided to rename the right-click 'Games' list menu for 'Updated' to 'Updated or Updates'. And some of the entries under that were also renamed slightly, plus I added a new entry called 'Information'.

All of that was with the aim of making dealing with Updates clearer. The 'Information' entry even has some instructions on the dialog that pops up.

DOWNLOAD

Enjoy!

BIG THANK YOU to Magnitus as always, for his excellent gogcli.exe program.

P.S. I am hoping to create a basic tutorial for my GUI soon, that basically describes, with pictures, how I generally use my GUI. The aim of that is to show users how to best leverage my GUI program ... updating the Games list, adding to the Manifest, setting up Downloads, dealing with Downloads, and how best to deal with Updates, etc.

I've started the basic tutorial ... only text at this stage, and incomplete.

Even so, you may find it helpful in its present state, and can download it as a HTML (web) file, to open in your browser. It does cover up to the download stage.

NOTE - This is not a setup tutorial. It presumes you have already done that.

DOWNLOAD

ADVICE
If you do need a setup tutorial, the older more comprehensive, though somewhat out-of-date tutorial with pictures, does still exist at GitHub. That should get you through the basics to some degree.

I've now added Steps 7 through 13 to my tutorial.

No images yet, but that will likely be next.

Use the same download link as in my previous post.

Enjoy!

P.S. I am also considering redoing my Setup tutorial. But the main changes, aside from using curl.exe now, would likely just be the browser extension (Get cookies.txt LOCALLY) I use to get the cookie file data. Optionally, there could be instructions for those brave enough to try and get Free Download Manager 5 working as the downloader ... though using aria2c.exe would likely be much easier.

I've now added many images (screenshots) to my tutorial ... including a screenshot of my Setup.

Same download link as previous (two posts back).

Was a bit of a coding exercise for me, as I learnt how to convert PNG images to Base64 data, and insert that in the html in place of the images. In fact I developed a helper program to do all that.

The images have increased the file size quite a bit, and a bit more for the Base64 variants. Less than 2 Mb overall though, so not onerous.

Enjoy!

P.S. I'll probably do something about including a couple of handy complimentary programs and their instructions next.

I probably should have mentioned this before, that I don't recommend downloading to the same game folder location as your storage one. Or you can, but you should put all the text files inside another sub-folder (i.e. Texts). This doesn't mean you need to use another drive, though I'd probably recommend that ... but then you might already be doing another copy to a backup drive anyway.

----------------------------------------------------------------------------

Here's download links to a couple of those handy programs I mentioned last post.

GOG Folders v1.3 - DOWNLOAD (updated)
new screenshot

This is just a standalone version of the popup window you get with the SUB button on my GUI.
So instructions for that are mostly the same.

Combine Or Replace v1.2 - DOWNLOAD

This helps with combining the text files of a game download with the updated versions.
I'll provide some detailed instructions (and images) in the tutorial at the end, but some basics here now below.

(1) Basically, you drag & drop the older 'Updates' or 'Texts' or game folder onto the green Destination label. That should reveal the following text files - Changelog.txt, Description.txt, Validation.txt and Serials.txt as well if that exists, plus the Folder.jpg file. NOTE - If none of those files exist in either folder, then you don't need to use this program yet ... just manually copy the new 'Updates' folder to the game folder, along with any relevant other files and folders (DLC, Soundtrack, Extras).

(2) You then need to drag & drop the newer 'Updates' folder of your recent update download for the game, to the blue ADD Source label.. The files will then be compared, and either skipped (if the same), or replaced or added to. Beyond that, you then manually copy your EXE and BIN files (game update) to the original game folder, along with any Extras and DLCs etc.

(the response from github that you said that you couldn't make any sense out of it)
Hello, I'm sorry for being late but I was kinda busy with my life and sometimes I forgot to reply to this, will check out the fixes and similar, soon. And, when I will still have problems with it, I will send you a list of the folders you asked for, and if I will have no problem with it anymore, I will just let you know.
P.S. I kinda feel bad that you do such a service and I couldn't find time for that. Also, I can say that your work is for sure great and that u put a lot of effort to it :)