I am going to be carrying cash and traveler checks in austria. ATM cards from Pakistani Banks dont always work in europe even for banks like standard chartered etc. I know why ATMs are preferrable. The question is simply is it safe to carry cash in austria? at all times of the day? at all places in vienna or other cities?? Thanks.

Austria is as safe as any other place. Use the same common sense and precautions one would always use and you'll be fine. I usually don't recommend TC's, but if the ATM isn't an option, this might be the next best thing.

Use a good moneybelt and keep a little cash in your pocket. Vienna is very safe, but you do need to watch out around the big tourist spots for pickpockets.

I have always carried cash around Austria, including Vienna, Graz, and Salzburg and never felt the worry about pickpockets that I've felt in other places. Of course, I'm sure there are some, but Vienna is overall a very safe place. There were a few ubahn stops that have a good share of grubby characters esp at night (Karlsplatz, for example), so I paid extra attention there, but the stops also had plenty of police around.
Overall, I found Vienna to be one of the safest big cities I've ever been to, at least in the city's core.

Karlsplatz at night is mostly druggies and other types. What is happening now is that Vienna gets daytrippers from the Eastern countries who do work at the pickpocket trade, my mother in-law got hit by a team of 4 on the U3 and didn't realize a thing till they got off on the next stop. I agree that Vienna, and I've been to all areas, is probably the safest city in Europe (or the world), but it still pays to be aware, though not paranoid. Robbery is almost unheard of there.

In addition to Karlsplatz at night, also be careful in the underground subway passages around Karlsplatz, and around the larger train stations (Westbahnhof, Sudbahnof).
On the whole, though, I agree with previous posters about the safety of Vienna and Austria in particular.

Regarding traveler's checks, be advised that Austria's banks will charge high fees (6-8%) just to cash the checks, in addition to the usually poor exchange rates for either traveler's checks or cash.
Are you sure you can't obtain an internationally recognized bank card? If you can't use it at an ATM, perhaps you can use it for an over-the-counter cash withdrawal inside the bank.