How can I effectively solo the co-op mode?

Is there a good way to solo the co-op mode? This seems like a contradiction, but I find myself frequently either the last man standing or the only player left after others quit or are disconnected. In other games, like Halo: Reach, it was feasible to even start a single-player "firefight" session and survive for dozens of rounds, but I find myself curb stomped nearly immediately in this game.

What can I do to make the best of this situation? Is there any hope for my survival?

Me soloing Bronze as a Human infiltrator, all my points in everything but cryo blast, using Black widow and M-3 Predator. I used no equipment but had to use medi-gels and rockets becuase lucky me had 3 hacking missions on my solo..sigh

There are many factors that would come into play that will assist you in completeing a Bronze mission solo:

• Being level ~20 is going to be almost necessary as you are gonna need every available power upgraded as much as possible to give you the advantages you will need.
• The right weapons per your class that you use and the know how when it comes to using your powers.
• Playing a map you are definately familiar with, making sure you know all the ammo locations and every important choke point on the map so you can grab ammo without delay as you move to the next choking point to funnel the enemies through.
• Not being afraid to use your rockets and medi-gels as well as making sure you dont waste them unecessarily, saving your rockets for the 10th and 11th waves where you will find yourself overwhelmed by heavy units and really no way to retreat.
• Plan ahead, dont run around finding a good spot to setup shop. Have a plan, when you feel like you are being make sure you know where you are going next and what path to take to avoid enemies.
• Never be without ammo, having to rely on powers works for a lot of classes but have no ammo can be deadly.
• Know the class you are playing, there is nothing more deadly then playing a character you only have the basic grasp of.
• Fight against the enemy your class has advantages against, i.e. dont bring Sabotage to a Reaper fight.

Adept: Crowd control from stasis (make sure you get Rank 6:Bubble) or singularity and a little bit of combination from warp you will have a serious advantage over a multitude of solders. Using warp and throw in combination on units such as Ravagers, Brutes, Banshees, Atlas', and Geth Primes to create a biotic explosion and you will tear through their armored health. if you use the weapons M-12 locust with the mod SMG Ultralight Material and the M-3 Predator the weight of the weapons will not affect your power recharge percentage allowing you the ability to lay down some fire on the little guys.

Infiltrator: Having a semi-automatic sniper rifle is desirable in this case, allowing you to headshot multiple enemies and thinning the crowds. Make sure that your tactical cloak is specced Rank 4 damage Increase damage bonus by 30%, Rank 5 Recharge Speed Increase recharge speed by 30%, Rank 6 Sniper Damage Increase sniper rifle damage by 40% while cloaked. As well as speccing into sheilds and health bonuses. bringing along a light pistol will come in handy for close quarters as you race to each position, putting distance between your enemies.

Vanguard: Vanguards obviously rely completely on their powers to inflict massive damage to their enemies. Ultimately this character is incredible powerful but extremely risky when you are alone and dont have allies to lay down covering fire. I would suggest constantly having caution and never stay out of cover for more then a couple hits before rushing to safety. Dont be afraid to fire a couple quick headshots to remove a couple of the stray buggers that get back up after your wave of destruction.

Engineer: Another power class that only excels with constant casting of powers. stay behind cover while always having your drone/turret/decoy up to distract them from firing upon you as you launch power after power into the crowds. Make sure you have a high power recharge and only carry light weapons as you will not be needing them extensively. Keeping in mind all the strategy tips i mentioned before you shall survive.

Sentinal: These guys are great at surviving and have an amazing panic button when you get surrounded. Have your tech armor upgraded to increase damage reduction so you can continuously lay down heavy fire on your enemies so they dont get the upper hand on you. These guys you dont have to worry so much about power recharge so you get to pick any number of weapon combinations to keep up the heavy damage.

Soldier: An incredibly versatile character with a decent survivability. The races for soldiers are incredibly different from eachother and obviously have their advantages. Krogans have increased defensive capabilites and Turians have increased fire rate. Use whatever weapons you are comfortable with and you will be fine.

little update for you, I found a couple videos for you they completed bronze solo. sentinals , vanguards , Engineers and Infiltrator

A solo Quarian Infiltrator can solo Geth enemies with relative ease, provided you can aim a sniper rifle. Quarian Infiltrator has a couple major advantages, especially against Geth.

Sabotage: this skill causes major problems to Geth, making them easier to kill and making them attack their allies (or at least they stop shooting you). It has a small AOE too, so try and hit tight clusters of Geth. Target Geth Hunters or Rocket Troopers to make the most of it. It even works on Geth Primes (which are your only major obstacle here), but a fair % of the time Geth Primes shrug it off. Leave Geth Primes for last, otherwise the other Geth will tear you apart.

Tactical Cloak: This is what keeps you alive. When Cloak is active, enemies will immediately stop attacking you and can't see you. Take this time to snipe Geth; aim for the head, headshots still hurt Geth extra. Cloak lets you run like hell or take clean headshots with your Sniper Rifle. It can let you get some good Shotgun shots in too, but Shotguns are too risky in solo.

Items: You're likely going to have to use the Equipment items like Medigel or the Missile Launcher to survive in some cases. Don't be afraid to take out the biggest baddies with a Missile. The shield/health instant heal can be a life saver in tough spots too.

Weapons: Take a sniper rifle and nothing else; you need to be light weight to keep your Tactical Cloak and Sabotage ready. Take the sniper you're most comfortable using, but the Black Widow or anything Semiautomatic are your friend as you can keep firing and get more headshots in less time. The Mantis is too slow between shots unless you've got perfect aim, and even then it's risky.

Objectives: These will be by far the hardest part. Assassination is easy (it's what you're made for!) but hacking will be extremely difficult and the "activate 4 nodes" bits will be tricky. Try Hit and Run tactics to keep enemies away from your objectives, but once you've got a Geth Prime/Banshee/Atlas after you and you're trying to hack, it's probably Game Over.