diff --git a/libs/remix-lib/src/execution/txRunner.ts b/libs/remix-lib/src/execution/txRunner.ts
index fd288b35eb..ddc2456fb5 100644
--- a/libs/remix-lib/src/execution/txRunner.ts
+++ b/libs/remix-lib/src/execution/txRunner.ts
@@ -111,6 +111,10 @@ export class TxRunner {
       return callback('Invalid account selected')
     }
 
+    if (Number.isInteger(gasLimit)) {
+      gasLimit = '0x' + gasLimit.toString(16)
+    }
+
     this.executionContext.vm().stateManager.getAccount(Address.fromString(from)).then((res) => {
       // See https://github.com/ethereumjs/ethereumjs-tx/blob/master/docs/classes/transaction.md#constructor
       // for initialization fields and their types
@@ -150,8 +154,8 @@ export class TxRunner {
           })
         })
       }
-    }).catch(() => {
-      callback('Account not found')
+    }).catch((e) => {
+      callback(e)
     })
   }
 
diff --git a/libs/remix-simulator/src/genesis.ts b/libs/remix-simulator/src/genesis.ts
index a0a20cec78..e7176e8a77 100644
--- a/libs/remix-simulator/src/genesis.ts
+++ b/libs/remix-simulator/src/genesis.ts
@@ -2,17 +2,20 @@ import { Block } from '@ethereumjs/block'
 import { BN } from 'ethereumjs-util'
 
 export function generateBlock (executionContext) {
-  const block: Block = Block.fromBlockData({
-    header: {
-      timestamp: (new Date().getTime() / 1000 | 0),
-      number: 0,
-      coinbase: '0x0e9281e9c6a0808672eaba6bd1220e144c9bb07a',
-      difficulty: new BN('69762765929000', 10),
-      gasLimit: new BN('8000000').imuln(1)
-    }
-  }, { common: executionContext.vmObject().common })
-
-  executionContext.vm().runBlock({ block: block, generate: true, skipBlockValidation: true, skipBalance: false }).then(() => {
-    executionContext.addBlock(block)
-  })
+  return new Promise((resolve, reject) => {
+    const block: Block = Block.fromBlockData({
+      header: {
+        timestamp: (new Date().getTime() / 1000 | 0),
+        number: 0,
+        coinbase: '0x0e9281e9c6a0808672eaba6bd1220e144c9bb07a',
+        difficulty: new BN('69762765929000', 10),
+        gasLimit: new BN('8000000').imuln(1)
+      }
+    }, { common: executionContext.vmObject().common })
+  
+    executionContext.vm().runBlock({ block: block, generate: true, skipBlockValidation: true, skipBalance: false }).then(() => {
+      executionContext.addBlock(block)
+      resolve({})
+    }).catch((e) => reject(e))
+  })  
 }
diff --git a/libs/remix-simulator/src/methods/blocks.ts b/libs/remix-simulator/src/methods/blocks.ts
index fc66a22892..bfed840284 100644
--- a/libs/remix-simulator/src/methods/blocks.ts
+++ b/libs/remix-simulator/src/methods/blocks.ts
@@ -31,6 +31,9 @@ export class Blocks {
       blockIndex = this.executionContext.latestBlockNumber
     }
 
+    if (Number.isInteger(blockIndex)) {
+      blockIndex = '0x' + blockIndex.toString(16)
+    }
     const block = this.executionContext.blocks[blockIndex]
 
     if (!block) {
@@ -57,7 +60,6 @@ export class Blocks {
       transactions: block.transactions.map((t) => '0x' + t.hash().toString('hex')),
       uncles: []
     }
-
     cb(null, b)
   }
 
diff --git a/libs/remix-simulator/src/provider.ts b/libs/remix-simulator/src/provider.ts
index afd6696a17..b5c62daa4f 100644
--- a/libs/remix-simulator/src/provider.ts
+++ b/libs/remix-simulator/src/provider.ts
@@ -38,13 +38,12 @@ export class Provider {
     this.methods = merge(this.methods, (new Filters(this.executionContext)).methods())
     this.methods = merge(this.methods, netMethods())
     this.methods = merge(this.methods, this.Transactions.methods())
-    this.methods = merge(this.methods, (new Debug(this.executionContext)).methods())
-
-    generateBlock(this.executionContext)
-    this.init()
+    this.methods = merge(this.methods, (new Debug(this.executionContext)).methods())    
+    // this.init()
   }
 
   async init () {
+    await generateBlock(this.executionContext)
     await this.Accounts.resetAccounts()
     this.Transactions.init(this.Accounts.accounts)
   }
diff --git a/libs/remix-simulator/test/accounts.ts b/libs/remix-simulator/test/accounts.ts
index 471cacfd72..0c36c38191 100644
--- a/libs/remix-simulator/test/accounts.ts
+++ b/libs/remix-simulator/test/accounts.ts
@@ -5,8 +5,9 @@ const web3 = new Web3()
 import * as assert from 'assert'
 
 describe('Accounts', () => {
-  before(function () {
+  before(async function () {
     const provider = new Provider()
+    await provider.init()
     web3.setProvider(provider)
   })
 
diff --git a/libs/remix-simulator/test/blocks.ts b/libs/remix-simulator/test/blocks.ts
index 5a404ee722..827c4dc726 100644
--- a/libs/remix-simulator/test/blocks.ts
+++ b/libs/remix-simulator/test/blocks.ts
@@ -5,10 +5,11 @@ const web3 = new Web3()
 import * as assert from 'assert'
 
 describe('blocks', () => {
-  before(() => {
+  before(async () => {
     const provider = new Provider('vm', {
       coinbase: '0x0000000000000000000000000000000000000001'
     })
+    await provider.init()
     web3.setProvider(provider)
   })
 
@@ -29,7 +30,7 @@ describe('blocks', () => {
         parentHash: '0x0000000000000000000000000000000000000000000000000000000000000000',
         sha3Uncles: '0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347',
         size: 163591,
-        stateRoot: '0x63e1738ea12d4e7d12b71f0f4604706417921eb6a62c407ca5f1d66b9e67f579',
+        stateRoot: '0x0000000000000000000000000000000000000000000000000000000000000000',
         timestamp: block.timestamp,
         totalDifficulty: '0',
         transactions: [],
diff --git a/libs/remix-simulator/test/misc.ts b/libs/remix-simulator/test/misc.ts
index 6d8f57ef49..cf38ce8740 100644
--- a/libs/remix-simulator/test/misc.ts
+++ b/libs/remix-simulator/test/misc.ts
@@ -5,8 +5,9 @@ const web3 = new Web3()
 import * as assert from 'assert'
 
 describe('Misc', () => {
-  before(() => {
+  before(async () => {
     const provider = new Provider()
+    await provider.init()
     web3.setProvider(provider)
   })