diff --git a/README.md b/README.md
index b2afaa08..0adc54ee 100644
--- a/README.md
+++ b/README.md
@@ -51,6 +51,7 @@ $ myth analyze -a <contract-address>
 Specify the maximum number of transaction to explore with `-t <number>`. You can also set a timeout with `--execution-timeout <seconds>`. Example ([source code](https://gist.github.com/b-mueller/2b251297ce88aa7628680f50f177a81a#file-killbilly-sol)):
 
 ```
+> myth a killbilly.sol -t 3
 ==== Unprotected Selfdestruct ====
 SWC ID: 106
 Severity: High
diff --git a/mythril/laser/ethereum/call.py b/mythril/laser/ethereum/call.py
index 5ad1943c..7be156d0 100644
--- a/mythril/laser/ethereum/call.py
+++ b/mythril/laser/ethereum/call.py
@@ -28,6 +28,7 @@ to get the necessary elements from the stack and determine the parameters for th
 """
 
 log = logging.getLogger(__name__)
+SYMBOLIC_CALLDATA_SIZE = 320  # Used when copying symbolic calldata
 
 
 def get_call_parameters(
@@ -178,6 +179,8 @@ def get_call_data(
             else memory_size
         ),
     )
+    if memory_size.symbolic:
+        memory_size = SYMBOLIC_CALLDATA_SIZE
     try:
         calldata_from_mem = state.memory[
             util.get_concrete_int(memory_start) : util.get_concrete_int(
diff --git a/mythril/laser/ethereum/instructions.py b/mythril/laser/ethereum/instructions.py
index 9ace7cac..e2b5bedf 100644
--- a/mythril/laser/ethereum/instructions.py
+++ b/mythril/laser/ethereum/instructions.py
@@ -35,7 +35,12 @@ from mythril.laser.ethereum.state.calldata import ConcreteCalldata, SymbolicCall
 import mythril.laser.ethereum.util as helper
 from mythril.laser.ethereum import util
 from mythril.laser.ethereum.keccak_function_manager import keccak_function_manager
-from mythril.laser.ethereum.call import get_call_parameters, native_call, get_call_data
+from mythril.laser.ethereum.call import (
+    get_call_parameters,
+    native_call,
+    get_call_data,
+    SYMBOLIC_CALLDATA_SIZE,
+)
 from mythril.laser.ethereum.evm_exceptions import (
     VmException,
     StackUnderflowException,
@@ -812,7 +817,7 @@ class Instruction:
             size = util.get_concrete_int(size)  # type: Union[int, BitVec]
         except TypeError:
             log.debug("Unsupported symbolic size in CALLDATACOPY")
-            size = 320  # The excess size will get overwritten
+            size = SYMBOLIC_CALLDATA_SIZE  # The excess size will get overwritten
 
         size = cast(int, size)
         if size > 0:
@@ -2188,7 +2193,6 @@ class Instruction:
                     global_state.new_bitvec("retval_" + str(instr["address"]), 256)
                 )
                 return [global_state]
-
         except ValueError as e:
             log.debug(
                 "Could not determine required parameters for call, putting fresh symbol on the stack. \n{}".format(
diff --git a/mythril/mythril/mythril_config.py b/mythril/mythril/mythril_config.py
index 174e47e5..e7f4463b 100644
--- a/mythril/mythril/mythril_config.py
+++ b/mythril/mythril/mythril_config.py
@@ -192,11 +192,14 @@ class MythrilConfig:
 
             if m and m.group(1) in ["mainnet", "rinkeby", "kovan", "ropsten"]:
                 if self.infura_id in (None, ""):
-                    raise CriticalError(
-                        "Infura key not provided. Use --infura-id <INFURA_ID> "
+                    log.info(
+                        "Infura key not provided, so onchain access is disabled. "
+                        "Use --infura-id <INFURA_ID> "
                         "or set it in the environment variable INFURA_ID "
-                        "or in the ~/.mythril/config.ini file'"
+                        "or in the ~/.mythril/config.ini file"
                     )
+                    self.eth = None
+                    return
 
                 rpcconfig = (
                     "{}.infura.io/v3/{}".format(m.group(1), self.infura_id),