JaariAtmc

Tekkit doesn't work on java 17, use java 8 for that instead.

Migrate your mojang account to a microsoft account.

Does this player have a mojang or microsoft account?

Microsoft enforces the use of microsoft accounts now. Mojang accounts are no longer usable for multiplayer minecraft. Yes, you get the generic invalid session error instead of something more descriptive.

Microsoft has started to enforce Microsoft accounts only. Mojang accounts no longer work for multiplayer. Instead of actually giving an error that helps people understand this, you get the generic invalid session.

Issue with vanilla minecraft, any version of minecraft between atleast 1.2 and 1.7 is affected by this. Minecraft 1.8+ does not have this issue. Fix this by downgrading your graphics driver to this version https://www.intel.com/content/www/us/en/download/19344/685037/intel-graphics-windows-dch-drivers.html or if you have an NVIDIA graphics card tell it via the control panel to run java/javaw on that instead.

For your first question: Yes, see here: https://fabricmc.net/wiki/tutorial:technic_modpacks For your second question: Not that I am aware of.

Yes, the cause has been identified for that, and it only affects minecraft up to 1.7.10 it seems. Do you have a dedicated graphics card in your computer, or do you only have an Intel HD graphics (which is a built-in gpu on your cpu)? If the first case, make sure that your dedicated graphics card runs minecraft. If the second case, downgrade your Intel graphics drivers to: https://www.intel.com/content/www/us/en/download/19344/685037/intel-graphics-windows-dch-drivers.html

Don't necro a 7 year old thread, leave it dead, make your own post. Or just look through my posting history here.

He can't select more than 3.5 GB if he doesn't have more physical ram inside his pc.

Please downgrade your intel drivers to this version. Yes, it will say that there's a newer version, the newer versions are what caused the problem. https://www.intel.com/content/www/us/en/download/19344/685037/intel-graphics-windows-dch-drivers.html

Do you only have a intel cpu with intel HD graphics in your laptop? Or do you happen to have a dedicated gpu in there as well. No, the version.json has absolutely nothing to do with this. I wish it was just white so people stop quoting it all the effing time.

Yes. Did you remove the older version of CoFHCore that was already included in the modpack? CoFHCore-[1.7.10]3.0.3-303 (1), to be exact.

Could you quote the names of the mods you included? Full name of it, please.

So which versions did you include? Did you check the version's forge requirement vs the modpack's included forge?

Looks like that's a botched attempt to make a curseforge modpack into a technic modpack. Forge has not been included in the bin folder.

Shift.

This modpack requires manually updating CodeChickenCore to the latest version. https://www.curseforge.com/minecraft/mc-mods/codechickencore/files/3293859 A dependency used to be downloaded automatically by the version included, but that download broke. Ultra Modded Survival is a community made modpack and was never updated to fix this.

"Any mod" aka "this one modpack that broke their download link".

This belongs in Platform Pagoda. Any inkling on what the name of your modpack is?

You have a paid minecraft account... right?

This modpack consists of a random assortment of mods and forge installers for minecraft 1.7.2, minecraft 1.7.10, minecraft 1.8, 1.9 and 1.12.2. This will never ever work in this format.

You are trying to allocate an amount of RAM you currently do not have available.

What are your main control keys set to? Especially your sneak key.